Programs & Examples On #Aggregate

Aggregate refers to the process of summarizing grouped data, commonly used in Statistics.

data.frame Group By column

require(reshape2)

T <- melt(df, id = c("A"))

T <- dcast(T, A ~ variable, sum)

I am not certain the exact advantages over aggregate.

Sql Server : How to use an aggregate function like MAX in a WHERE clause

yes you need to use a having clause after the Group by clause , as the where is just to filter the data on simple parameters , but group by followed by a Having statement is the idea to group the data and filter it on basis of some aggregate function......

Aggregate / summarize multiple variables per group (e.g. sum, mean)

For a more flexible and faster approach to data aggregation, check out the collap function in the collapse R package available on CRAN:

library(collapse)
# Simple aggregation with one function
head(collap(df1, x1 + x2 ~ year + month, fmean))

  year month        x1        x2
1 2000     1 -1.217984  4.008534
2 2000     2 -1.117777 11.460301
3 2000     3  5.552706  8.621904
4 2000     4  4.238889 22.382953
5 2000     5  3.124566 39.982799
6 2000     6 -1.415203 48.252283

# Customized: Aggregate columns with different functions
head(collap(df1, x1 + x2 ~ year + month, 
      custom = list(fmean = c("x1", "x2"), fmedian = "x2")))

  year month  fmean.x1  fmean.x2 fmedian.x2
1 2000     1 -1.217984  4.008534   3.266968
2 2000     2 -1.117777 11.460301  11.563387
3 2000     3  5.552706  8.621904   8.506329
4 2000     4  4.238889 22.382953  20.796205
5 2000     5  3.124566 39.982799  39.919145
6 2000     6 -1.415203 48.252283  48.653926

# You can also apply multiple functions to all columns
head(collap(df1, x1 + x2 ~ year + month, list(fmean, fmin, fmax)))

  year month  fmean.x1    fmin.x1  fmax.x1  fmean.x2   fmin.x2  fmax.x2
1 2000     1 -1.217984 -4.2460775 1.245649  4.008534 -1.720181 10.47825
2 2000     2 -1.117777 -5.0081858 3.330872 11.460301  9.111287 13.86184
3 2000     3  5.552706  0.1193369 9.464760  8.621904  6.807443 11.54485
4 2000     4  4.238889  0.8723805 8.627637 22.382953 11.515753 31.66365
5 2000     5  3.124566 -1.5985090 7.341478 39.982799 31.957653 46.13732
6 2000     6 -1.415203 -4.6072295 2.655084 48.252283 42.809211 52.31309

# When you do that, you can also return the data in a long format
head(collap(df1, x1 + x2 ~ year + month, list(fmean, fmin, fmax), return = "long"))

  Function year month        x1        x2
1    fmean 2000     1 -1.217984  4.008534
2    fmean 2000     2 -1.117777 11.460301
3    fmean 2000     3  5.552706  8.621904
4    fmean 2000     4  4.238889 22.382953
5    fmean 2000     5  3.124566 39.982799
6    fmean 2000     6 -1.415203 48.252283

Note: You can use base functions like mean, max etc. with collap, but fmean, fmax etc. are C++ based grouped functions offered in the collapse package which are significantly faster (i.e. the performance on large data aggregations is the same as data.table while providing greater flexibility, and these fast grouped functions can also be used without collap).

Note2: collap also supports flexible multitype data aggregation, which you can of course do using the custom argument, but you can also apply functions to numeric and non-numeric columns in a semi-automated way:

# wlddev is a data set of World Bank Indicators provided in the collapse package
head(wlddev)

      country iso3c       date year decade     region     income  OECD PCGDP LIFEEX GINI       ODA
1 Afghanistan   AFG 1961-01-01 1960   1960 South Asia Low income FALSE    NA 32.292   NA 114440000
2 Afghanistan   AFG 1962-01-01 1961   1960 South Asia Low income FALSE    NA 32.742   NA 233350000
3 Afghanistan   AFG 1963-01-01 1962   1960 South Asia Low income FALSE    NA 33.185   NA 114880000
4 Afghanistan   AFG 1964-01-01 1963   1960 South Asia Low income FALSE    NA 33.624   NA 236450000
5 Afghanistan   AFG 1965-01-01 1964   1960 South Asia Low income FALSE    NA 34.060   NA 302480000
6 Afghanistan   AFG 1966-01-01 1965   1960 South Asia Low income FALSE    NA 34.495   NA 370250000

# This aggregates the data, applying the mean to numeric and the statistical mode to categorical columns
head(collap(wlddev, ~ iso3c + decade, FUN = fmean, catFUN = fmode))

  country iso3c       date   year decade                     region      income  OECD    PCGDP   LIFEEX GINI      ODA
1   Aruba   ABW 1961-01-01 1962.5   1960 Latin America & Caribbean  High income FALSE       NA 66.58583   NA       NA
2   Aruba   ABW 1967-01-01 1970.0   1970 Latin America & Caribbean  High income FALSE       NA 69.14178   NA       NA
3   Aruba   ABW 1976-01-01 1980.0   1980 Latin America & Caribbean  High income FALSE       NA 72.17600   NA 33630000
4   Aruba   ABW 1987-01-01 1990.0   1990 Latin America & Caribbean  High income FALSE 23677.09 73.45356   NA 41563333
5   Aruba   ABW 1996-01-01 2000.0   2000 Latin America & Caribbean  High income FALSE 26766.93 73.85773   NA 19857000
6   Aruba   ABW 2007-01-01 2010.0   2010 Latin America & Caribbean  High income FALSE 25238.80 75.01078   NA       NA

# Note that by default (argument keep.col.order = TRUE) the column order is also preserved

What are Aggregates and PODs and how/why are they special?

What changes in

Following the rest of the clear theme of this question, the meaning and use of aggregates continues to change with every standard. There are several key changes on the horizon.

Types with user-declared constructors P1008

In C++17, this type is still an aggregate:

struct X {
    X() = delete;
};

And hence, X{} still compiles because that is aggregate initialization - not a constructor invocation. See also: When is a private constructor not a private constructor?

In C++20, the restriction will change from requiring:

no user-provided, explicit, or inherited constructors

to

no user-declared or inherited constructors

This has been adopted into the C++20 working draft. Neither the X here nor the C in the linked question will be aggregates in C++20.

This also makes for a yo-yo effect with the following example:

class A { protected: A() { }; };
struct B : A { B() = default; };
auto x = B{};

In C++11/14, B was not an aggregate due to the base class, so B{} performs value-initialization which calls B::B() which calls A::A(), at a point where it is accessible. This was well-formed.

In C++17, B became an aggregate because base classes were allowed, which made B{} aggregate-initialization. This requires copy-list-initializing an A from {}, but from outside the context of B, where it is not accessible. In C++17, this is ill-formed (auto x = B(); would be fine though).

In C++20 now, because of the above rule change, B once again ceases to be an aggregate (not because of the base class, but because of the user-declared default constructor - even though it's defaulted). So we're back to going through B's constructor, and this snippet becomes well-formed.

Initializing aggregates from a parenthesized list of values P960

A common issue that comes up is wanting to use emplace()-style constructors with aggregates:

struct X { int a, b; };
std::vector<X> xs;
xs.emplace_back(1, 2); // error

This does not work, because emplace will try to effectively perform the initialization X(1, 2), which is not valid. The typical solution is to add a constructor to X, but with this proposal (currently working its way through Core), aggregates will effectively have synthesized constructors which do the right thing - and behave like regular constructors. The above code will compile as-is in C++20.

Class Template Argument Deduction (CTAD) for Aggregates P1021 (specifically P1816)

In C++17, this does not compile:

template <typename T>
struct Point {
    T x, y;
};

Point p{1, 2}; // error

Users would have to write their own deduction guide for all aggregate templates:

template <typename T> Point(T, T) -> Point<T>;

But as this is in some sense "the obvious thing" to do, and is basically just boilerplate, the language will do this for you. This example will compile in C++20 (without the need for the user-provided deduction guide).

ListAGG in SQLSERVER

Starting in SQL Server 2017 the STRING_AGG function is available which simplifies the logic considerably:

select FieldA, string_agg(FieldB, '') as data
from yourtable
group by FieldA

See SQL Fiddle with Demo

In SQL Server you can use FOR XML PATH to get the result:

select distinct t1.FieldA,
  STUFF((SELECT distinct '' + t2.FieldB
         from yourtable t2
         where t1.FieldA = t2.FieldA
            FOR XML PATH(''), TYPE
            ).value('.', 'NVARCHAR(MAX)') 
        ,1,0,'') data
from yourtable t1;

See SQL Fiddle with Demo

SQL Server : SUM() of multiple rows including where clauses

Use a common table expression to add grand total row, top 100 is required for order by to work.

With Detail as 
(
    SELECT  top 100 propertyId, SUM(Amount) as TOTAL_COSTS
    FROM MyTable
    WHERE EndDate IS NULL
    GROUP BY propertyId
    ORDER BY TOTAL_COSTS desc
)

Select * from Detail
Union all
Select ' Total ', sum(TOTAL_COSTS) from Detail

Count number of rows within each group

dplyr package does this with count/tally commands, or the n() function:

First, some data:

df <- data.frame(x = rep(1:6, rep(c(1, 2, 3), 2)), year = 1993:2004, month = c(1, 1:11))

Now the count:

library(dplyr)
count(df, year, month)
#piping
df %>% count(year, month)

We can also use a slightly longer version with piping and the n() function:

df %>% 
  group_by(year, month) %>%
  summarise(number = n())

or the tally function:

df %>% 
  group_by(year, month) %>%
  tally()

Aggregate multiple columns at once

You could try:

agg <- aggregate(list(x$val1, x$val2, x$val3, x$val4), by = list(x$id1, x$id2), mean)

Pandas sum by groupby, but exclude certain columns

You can select the columns of a groupby:

In [11]: df.groupby(['Country', 'Item_Code'])[["Y1961", "Y1962", "Y1963"]].sum()
Out[11]:
                       Y1961  Y1962  Y1963
Country     Item_Code
Afghanistan 15            10     20     30
            25            10     20     30
Angola      15            30     40     50
            25            30     40     50

Note that the list passed must be a subset of the columns otherwise you'll see a KeyError.

SQL Server "cannot perform an aggregate function on an expression containing an aggregate or a subquery", but Sybase can

One option is to put the subquery in a LEFT JOIN:

select sum ( t.graduates ) - t1.summedGraduates 
from table as t
    left join 
     ( 
        select sum ( graduates ) summedGraduates, id
        from table  
        where group_code not in ('total', 'others' )
        group by id 
    ) t1 on t.id = t1.id
where t.group_code = 'total'
group by t1.summedGraduates 

Perhaps a better option would be to use SUM with CASE:

select sum(case when group_code = 'total' then graduates end) -
    sum(case when group_code not in ('total','others') then graduates end)
from yourtable

SQL Fiddle Demo with both

SELECT list is not in GROUP BY clause and contains nonaggregated column

As @Brian Riley already said you should either remove 1 column in your select

select countrylanguage.language ,sum(country.population*countrylanguage.percentage/100)
from countrylanguage
join country on countrylanguage.countrycode = country.code
group by countrylanguage.language
order by sum(country.population*countrylanguage.percentage) desc ;

or add it to your grouping

select countrylanguage.language, country.code, sum(country.population*countrylanguage.percentage/100)
from countrylanguage
join country on countrylanguage.countrycode = country.code
group by countrylanguage.language, country.code
order by sum(country.population*countrylanguage.percentage) desc ;

How to sum a variable by group

You can also use the by() function:

x2 <- by(x$Frequency, x$Category, sum)
do.call(rbind,as.list(x2))

Those other packages (plyr, reshape) have the benefit of returning a data.frame, but it's worth being familiar with by() since it's a base function.

Summarizing multiple columns with dplyr?

For completeness: with dplyr v0.2 ddply with colwise will also do this:

> ddply(df, .(grp), colwise(mean))
  grp        a    b        c        d
1   1 4.333333 4.00 1.000000 2.000000
2   2 2.000000 2.75 2.750000 2.750000
3   3 3.000000 4.00 4.333333 3.666667

but it is slower, at least in this case:

> microbenchmark(ddply(df, .(grp), colwise(mean)), 
                  df %>% group_by(grp) %>% summarise_each(funs(mean)))
Unit: milliseconds
                                            expr      min       lq     mean
                ddply(df, .(grp), colwise(mean))     3.278002 3.331744 3.533835
 df %>% group_by(grp) %>% summarise_each(funs(mean)) 1.001789 1.031528 1.109337

   median       uq      max neval
 3.353633 3.378089 7.592209   100
 1.121954 1.133428 2.292216   100

Mean per group in a data.frame

A third great alternative is using the package data.table, which also has the class data.frame, but operations like you are looking for are computed much faster.

library(data.table)
mydt <- structure(list(Name = c("Aira", "Aira", "Aira", "Ben", "Ben", "Ben", "Cat", "Cat", "Cat"), Month = c(1L, 2L, 3L, 1L, 2L, 3L, 1L, 2L, 3L), Rate1 = c(15.6396600443877, 2.15649279424609, 6.24692918928743, 2.37658797276116, 34.7500663272292, 3.28750138697048, 29.3265553981065, 17.9821839334431, 10.8639802575958), Rate2 = c(17.1680489538369, 5.84231656330206, 8.54330866437461, 5.88415184986176, 3.02064294862551, 17.2053351400752, 16.9552950199166, 2.56058000170089, 15.7496228048122)), .Names = c("Name", "Month", "Rate1", "Rate2"), row.names = c(NA, -9L), class = c("data.table", "data.frame"))

Now to take the mean of Rate1 and Rate2 for all 3 months, for each person (Name): First, decide which columns you want to take the mean of

colstoavg <- names(mydt)[3:4]

Now we use lapply to take the mean over the columns we want to avg (colstoavg)

mydt.mean <- mydt[,lapply(.SD,mean,na.rm=TRUE),by=Name,.SDcols=colstoavg]

 mydt.mean
   Name     Rate1     Rate2
1: Aira  8.014361 10.517891
2:  Ben 13.471385  8.703377
3:  Cat 19.390907 11.755166

SQL JOIN, GROUP BY on three tables to get totals

Thank you very much for the replies!

Saggi Malachi, that query unfortunately sums the invoice amount in cases where there is more than one payment. Say there are two payments to a $39 invoice of $18 and $12. So rather than ending up with a result that looks like:

1   39.00   9.00

You'll end up with:

1   78.00   48.00

Charles Bretana, in the course of trimming my query down to the simplest possible query I (stupidly) omitted an additional table, customerinvoices, which provides a link between customers and invoices. This can be used to see invoices for which payments haven't made.

After much struggling, I think that the following query returns what I need it to:

SELECT DISTINCT i.invoiceid, i.amount, ISNULL(i.amount - p.amount, i.amount) AS amountdue
FROM invoices i
LEFT JOIN invoicepayments ip ON i.invoiceid = ip.invoiceid
LEFT JOIN customerinvoices ci ON i.invoiceid = ci.invoiceid
LEFT JOIN (
  SELECT invoiceid, SUM(p.amount) amount
  FROM invoicepayments ip 
  LEFT JOIN payments p ON ip.paymentid = p.paymentid
  GROUP BY ip.invoiceid
) p
ON p.invoiceid = ip.invoiceid
LEFT JOIN payments p2 ON ip.paymentid = p2.paymentid
LEFT JOIN customers c ON ci.customerid = c.customerid
WHERE c.customernumber='100'

Would you guys concur?

Count number of rows per group and add result to original data frame

You were just one step away from incorporating the row count into the base dataset.

Using the tidy() function from the broom package, convert the frequency table into a data frame and inner join with df:

df <- data.frame(name=c('black','black','black','red','red'),
                         type=c('chair','chair','sofa','sofa','plate'),
                         num=c(4,5,12,4,3))
library(broom)
df <- merge(df, tidy(table(df[ , c("name","type")])), by=c("name","type"))
df
   name  type num Freq
1 black chair   4    2
2 black chair   5    2
3 black  sofa  12    1
4   red plate   3    1
5   red  sofa   4    1

C# Linq Group By on multiple columns

Given a list:

var list = new List<Child>()
{
    new Child()
        {School = "School1", FavoriteColor = "blue", Friend = "Bob", Name = "John"},
    new Child()
        {School = "School2", FavoriteColor = "blue", Friend = "Bob", Name = "Pete"},
    new Child()
        {School = "School1", FavoriteColor = "blue", Friend = "Bob", Name = "Fred"},
    new Child()
        {School = "School2", FavoriteColor = "blue", Friend = "Fred", Name = "Bob"},
};

The query would look like:

var newList = list
    .GroupBy(x => new {x.School, x.Friend, x.FavoriteColor})
    .Select(y => new ConsolidatedChild()
        {
            FavoriteColor = y.Key.FavoriteColor,
            Friend = y.Key.Friend,
            School = y.Key.School,
            Children = y.ToList()
        }
    );

Test code:

foreach(var item in newList)
{
    Console.WriteLine("School: {0} FavouriteColor: {1} Friend: {2}", item.School,item.FavoriteColor,item.Friend);
    foreach(var child in item.Children)
    {
        Console.WriteLine("\t Name: {0}", child.Name);
    }
}

Result:

School: School1 FavouriteColor: blue Friend: Bob
    Name: John
    Name: Fred
School: School2 FavouriteColor: blue Friend: Bob
    Name: Pete
School: School2 FavouriteColor: blue Friend: Fred
    Name: Bob

How to use GROUP BY to concatenate strings in MySQL?

Great answers. I also had a problem with NULLS and managed to solve it by including a COALESCE inside of the GROUP_CONCAT. Example as follows:

SELECT id, GROUP_CONCAT(COALESCE(name,'') SEPARATOR ' ') 
FROM table 
GROUP BY id;

Hope this helps someone else

Select the top N values by group

You can write a function that splits the database by a factor, orders by another desired variable, extract the number of rows you want in each factor (category) and combine these into a database.

top<-function(x, num, c1,c2){
sorted<-x[with(x,order(x[,c1],x[,c2],decreasing=T)),]
splits<-split(sorted,sorted[,c1])
df<-lapply(splits,head,num)
do.call(rbind.data.frame,df)}

x is the dataframe;

num is the number of number of rows you would like to see;

c1 is the column number of the variable you would like to split by;

c2 is the column number of the variable you would like to rank by or handle ties.

Using the mtcars data, the function extracts the 3 heaviest cars (mtcars$wt is the 6th column) in each cylinder class (mtcars$cyl is the 2nd column)

 top(mtcars,3,2,6)
                         mpg cyl  disp  hp drat    wt  qsec vs am gear carb
 4.Merc 240D           24.4   4 146.7  62 3.69 3.190 20.00  1  0    4    2
 4.Merc 230            22.8   4 140.8  95 3.92 3.150 22.90  1  0    4    2
 4.Volvo 142E          21.4   4 121.0 109 4.11 2.780 18.60  1  1    4    2
 6.Valiant             18.1   6 225.0 105 2.76 3.460 20.22  1  0    3    1
 6.Merc 280            19.2   6 167.6 123 3.92 3.440 18.30  1  0    4    4
 6.Merc 280C           17.8   6 167.6 123 3.92 3.440 18.90  1  0    4    4
 8.Lincoln Continental 10.4   8 460.0 215 3.00 5.424 17.82  0  0    3    4
 8.Chrysler Imperial   14.7   8 440.0 230 3.23 5.345 17.42  0  0    3    4
 8.Cadillac Fleetwood  10.4   8 472.0 205 2.93 5.250 17.98  0  0    3    4

You can also easily get the lightest in a class by changing head in the lapply function to tail OR by removing the decreasing=T argument in the order function which will return it to its default, decreasing=F.

Performing a query on a result from another query?

Usually you can plug a Query's result (which is basically a table) as the FROM clause source of another query, so something like this will be written:

SELECT COUNT(*), SUM(SUBQUERY.AGE) from
(
  SELECT availables.bookdate AS Date, DATEDIFF(now(),availables.updated_at) as Age
  FROM availables
  INNER JOIN rooms
  ON availables.room_id=rooms.id
  WHERE availables.bookdate BETWEEN '2009-06-25' AND date_add('2009-06-25', INTERVAL 4 DAY) AND rooms.hostel_id = 5094
  GROUP BY availables.bookdate
) AS SUBQUERY

LINQ Aggregate algorithm explained

In addition to all the great answers here already, I've also used it to walk an item through a series of transformation steps.

If a transformation is implemented as a Func<T,T>, you can add several transformations to a List<Func<T,T>> and use Aggregate to walk an instance of T through each step.

A more concrete example

You want to take a string value, and walk it through a series of text transformations that could be built programatically.

var transformationPipeLine = new List<Func<string, string>>();
transformationPipeLine.Add((input) => input.Trim());
transformationPipeLine.Add((input) => input.Substring(1));
transformationPipeLine.Add((input) => input.Substring(0, input.Length - 1));
transformationPipeLine.Add((input) => input.ToUpper());

var text = "    cat   ";
var output = transformationPipeLine.Aggregate(text, (input, transform)=> transform(input));
Console.WriteLine(output);

This will create a chain of transformations: Remove leading and trailing spaces -> remove first character -> remove last character -> convert to upper-case. Steps in this chain can be added, removed, or reordered as needed, to create whatever kind of transformation pipeline is required.

The end result of this specific pipeline, is that " cat " becomes "A".


This can become very powerful once you realize that T can be anything. This could be used for image transformations, like filters, using BitMap as an example;

Pandas group-by and sum

A variation on the .agg() function; provides the ability to (1) persist type DataFrame, (2) apply averages, counts, summations, etc. and (3) enables groupby on multiple columns while maintaining legibility.

df.groupby(['att1', 'att2']).agg({'att1': "count", 'att3': "sum",'att4': 'mean'})

using your values...

df.groupby(['Name', 'Fruit']).agg({'Number': "sum"})

Compute mean and standard deviation by group for multiple variables in a data.frame

There is a helpful function in the psych package.

You should try the following implementation:

psych::describeBy(data$dependentvariable, group = data$groupingvariable)

Aggregate a dataframe on a given column and display another column

I don't have a high enough reputation to comment on Gavin Simpson's answer, but I wanted to warn that there seems to be a difference in the default treatment of missing values between the standard syntax and the formula syntax for aggregate.

#Create some data with missing values 
a<-data.frame(day=rep(1,5),hour=c(1,2,3,3,4),val=c(1,NA,3,NA,5))
  day hour val
1   1    1   1
2   1    2  NA
3   1    3   3
4   1    3  NA
5   1    4   5

#Standard syntax
aggregate(a$val,by=list(day=a$day,hour=a$hour),mean,na.rm=T)
  day hour   x
1   1    1   1
2   1    2 NaN
3   1    3   3
4   1    4   5

#Formula syntax.  Note the index for hour 2 has been silently dropped.
aggregate(val ~ hour + day,data=a,mean,na.rm=T)
  hour day val
1    1   1   1
2    3   1   3
3    4   1   5

Group By Multiple Columns

Procedural sample

.GroupBy(x => new { x.Column1, x.Column2 })

How to group dataframe rows into list in pandas groupby

If performance is important go down to numpy level:

import numpy as np

df = pd.DataFrame({'a': np.random.randint(0, 60, 600), 'b': [1, 2, 5, 5, 4, 6]*100})

def f(df):
         keys, values = df.sort_values('a').values.T
         ukeys, index = np.unique(keys, True)
         arrays = np.split(values, index[1:])
         df2 = pd.DataFrame({'a':ukeys, 'b':[list(a) for a in arrays]})
         return df2

Tests:

In [301]: %timeit f(df)
1000 loops, best of 3: 1.64 ms per loop

In [302]: %timeit df.groupby('a')['b'].apply(list)
100 loops, best of 3: 5.26 ms per loop

Extract the maximum value within each group in a dataframe

Using sqldf and standard sql to get the maximum values grouped by another variable

https://cran.r-project.org/web/packages/sqldf/sqldf.pdf

library(sqldf)
sqldf("select max(Value),Gene from df1 group by Gene")

or

Using the excellent Hmisc package for a groupby application of function (max) https://www.rdocumentation.org/packages/Hmisc/versions/4.0-3/topics/summarize

library(Hmisc)
summarize(df1$Value,df1$Gene,max)

Saving a select count(*) value to an integer (SQL Server)

select @myInt = COUNT(*) from myTable

Multiple aggregations of the same column using pandas GroupBy.agg()

Would something like this work:

In [7]: df.groupby('dummy').returns.agg({'func1' : lambda x: x.sum(), 'func2' : lambda x: x.prod()})
Out[7]: 
              func2     func1
dummy                        
1     -4.263768e-16 -0.188565

String formatting in Python 3

I like this approach

my_hash = {}
my_hash["goals"] = 3 #to show number
my_hash["penalties"] = "5" #to show string
print("I scored %(goals)d goals and took %(penalties)s penalties" % my_hash)

Note the appended d and s to the brackets respectively.

output will be:

I scored 3 goals and took 5 penalties

Why, Fatal error: Class 'PHPUnit_Framework_TestCase' not found in ...?

For me, it was because I ran

$ phpunit .

instead of

$ phpunit

when I already had a configured phpunit.xml file in the working directory.

Pure JavaScript equivalent of jQuery's $.ready() - how to call a function when the page/DOM is ready for it

Your method (placing script before the closing body tag)

<script>
   myFunction()
</script>
</body>
</html>

is a reliable way to support old and new browsers.

How to update primary key

If you are sure that this change is suitable for the environment you're working in: set the FK conditions on the secondary tables to UPDATE CASCADING.

For example, if using SSMS as GUI:

  1. right click on the key
  2. select Modify
  3. Fold out 'INSERT And UPDATE Specific'
  4. For 'Update Rule', select Cascade.
  5. Close the dialog and save the key.

When you then update a value in the PK column in your primary table, the FK references in the other tables will be updated to point at the new value, preserving data integrity.

How to make a JSONP request from Javascript without JQuery?

function foo(data)
{
    // do stuff with JSON
}

var script = document.createElement('script');
script.src = '//example.com/path/to/jsonp?callback=foo'

document.getElementsByTagName('head')[0].appendChild(script);
// or document.head.appendChild(script) in modern browsers

MVC Calling a view from a different controller

To directly answer your question if you want to return a view that belongs to another controller you simply have to specify the name of the view and its folder name.

public class CommentsController : Controller
{
    public ActionResult Index()
    { 
        return View("../Articles/Index", model );
    }
}

and

public class ArticlesController : Controller
{
    public ActionResult Index()
    { 
        return View();
    }
}

Also, you're talking about using a read and write method from one controller in another. I think you should directly access those methods through a model rather than calling into another controller as the other controller probably returns html.

Check if item is in an array / list

You can also use the same syntax for an array. For example, searching within a Pandas series:

ser = pd.Series(['some', 'strings', 'to', 'query'])

if item in ser.values:
    # do stuff

phpinfo() is not working on my CentOS server

Try to create a php.ini file in root and write the following command in and save it.

disable_functions =

Using this code will enable the phpinfo() function for you if it is disabled by the global PHP configuration.

Fatal error: Uncaught Error: Call to undefined function mysql_connect()

in case of a similar issue when I'm creating dockerfile I faced the same scenario:- I used below changed in mysql_connect function as:-

if($CONN = @mysqli_connect($DBHOST, $DBUSER, $DBPASS)){ //mysql_query("SET CHARACTER SET 'gbk'", $CONN);

how to disable DIV element and everything inside

The following css statement disables click events

pointer-events:none;

Reading PDF content with itextsharp dll in VB.NET or C#

Here is a VB.NET solution based on ShravankumarKumar's solution.

This will ONLY give you the text. The images are a different story.

Public Shared Function GetTextFromPDF(PdfFileName As String) As String
    Dim oReader As New iTextSharp.text.pdf.PdfReader(PdfFileName)

    Dim sOut = ""

    For i = 1 To oReader.NumberOfPages
        Dim its As New iTextSharp.text.pdf.parser.SimpleTextExtractionStrategy

        sOut &= iTextSharp.text.pdf.parser.PdfTextExtractor.GetTextFromPage(oReader, i, its)
    Next

    Return sOut
End Function

Getting strings recognized as variable names in R

The basic answer to the question in the title is eval(as.symbol(variable_name_as_string)) as Josh O'Brien uses. e.g.

var.name = "x"
assign(var.name, 5)
eval(as.symbol(var.name)) # outputs 5

Or more simply:

get(var.name) # 5

Failed to create provisioning profile

For me this happened when I was making a tvOS app and didn't have a appleTV registered.

In general, you need to plug in the device or have logged into it (connected to it)..then it shows up here: https://developer.apple.com/account/resources/devices/list

You can also add devices there..you need to click reset to be able to add a new device. the reset button should be labeled modify because it doesn't reset anything.

for example, if you need to make a tvOS app then you need to have an apple TV in the device list. Once you add that then you're good to go. kisses.

How to delete session cookie in Postman?

As @markus said use the "Cookie Manager" and delete the cookie. enter image description here

If you want to learn how to set destroy cookies in postman, You should check the Postman Echo service https://docs.postman-echo.com/

There you will find complete explanation on how to Set, Get and Delete those cookies.

Check it on : https://docs.postman-echo.com/#3de3b135-b3cc-3a68-ba27-b6d373e03c8c

Give it a Try.

Is there a way to "limit" the result with ELOQUENT ORM of Laravel?

If you're looking to paginate results, use the integrated paginator, it works great!

$games = Game::paginate(30);
// $games->results = the 30 you asked for
// $games->links() = the links to next, previous, etc pages

How can I check if a checkbox is checked?

Try this:

function validate() {
  var remember = document.getElementById("remember");
  if (remember.checked) {
    alert("checked");
  } else {
    alert("You didn't check it! Let me check it for you.");
  }
}

Your script doesn't know what the variable remember is. You need to get the element first using getElementById().

Jquery UI tooltip does not support html content

To expand on @Andrew Whitaker's answer above, you can convert your tooltip to html entities within the title tag so as to avoid putting raw html directly in your attributes:

_x000D_
_x000D_
$('div').tooltip({_x000D_
    content: function () {_x000D_
        return $(this).prop('title');_x000D_
    }_x000D_
});
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.8.3/jquery.min.js"></script>_x000D_
<script src="http://code.jquery.com/ui/1.9.2/jquery-ui.js"></script>_x000D_
<div class="tooltip" title="&lt;div&gt;check out these kool &lt;i&gt;italics&lt;/i&gt; and this &lt;span style=&quot;color:red&quot;&gt;red text&lt;/span&gt;&lt;/div&gt;">Hover Here</div>
_x000D_
_x000D_
_x000D_

More often than not, the tooltip is stored in a php variable anyway so you'd only need:

<div title="<?php echo htmlentities($tooltip); ?>">Hover Here</div>

Remove files from Git commit

Just wanted to complement the top answer as I had to run an extra command:

git reset --soft HEAD^
git checkout origin/master <filepath>

Cheers!

Python - 'ascii' codec can't decode byte

You use u"??".encode('utf8') to encode an unicode string. But if you want to represent "??", you should decode it. Just like:

"??".decode("utf8")

You will get what you want. Maybe you should learn more about encode & decode.

Cannot resolve symbol HttpGet,HttpClient,HttpResponce in Android Studio

please add these codes to your dependencies. It will work.

implementation 'org.jbundle.util.osgi.wrapped:org.jbundle.util.osgi.wrapped.org.apache.http.client:4.1.2'
dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    testCompile 'junit:junit:4.12'
    implementation 'com.android.support:appcompat-v7:23.1.0'
    implementation 'com.android.support:design:23.1.0'
    implementation 'com.android.support:cardview-v7:23.1.0'
    implementation 'com.android.support:recyclerview-v7:23.1.0'

    implementation 'org.jbundle.util.osgi.wrapped:org.jbundle.util.osgi.wrapped.org.apache.http.client:4.1.2'
}

Completely remove MariaDB or MySQL from CentOS 7 or RHEL 7

These steps are working on CentOS 6.5 so they should work on CentOS 7 too:

(EDIT - exactly the same steps work for MariaDB 10.3 on CentOS 8)

  1. yum remove mariadb mariadb-server
  2. rm -rf /var/lib/mysql If your datadir in /etc/my.cnf points to a different directory, remove that directory instead of /var/lib/mysql
  3. rm /etc/my.cnf the file might have already been deleted at step 1
  4. Optional step: rm ~/.my.cnf
  5. yum install mariadb mariadb-server

[EDIT] - Update for MariaDB 10.1 on CentOS 7

The steps above worked for CentOS 6.5 and MariaDB 10.

I've just installed MariaDB 10.1 on CentOS 7 and some of the steps are slightly different.

Step 1 would become:

yum remove MariaDB-server MariaDB-client

Step 5 would become:

yum install MariaDB-server MariaDB-client

The other steps remain the same.

Spring not autowiring in unit tests with JUnit

You need to use the Spring JUnit runner in order to wire in Spring beans from your context. The code below assumes that you have a application context called testContest.xml available on the test classpath.

import org.hibernate.SessionFactory;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
import org.springframework.transaction.annotation.Transactional;

import java.sql.SQLException;

import static org.hamcrest.MatcherAssert.assertThat;
import static org.hamcrest.Matchers.startsWith;

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = {"classpath*:**/testContext.xml"})
@Transactional
public class someDaoTest {

    @Autowired
    protected SessionFactory sessionFactory;

    @Test
    public void testDBSourceIsCorrect() throws SQLException {
        String databaseProductName = sessionFactory.getCurrentSession()
                .connection()
                .getMetaData()
                .getDatabaseProductName();
        assertThat("Test container is pointing at the wrong DB.", databaseProductName, startsWith("HSQL"));
    }
}

Note: This works with Spring 2.5.2 and Hibernate 3.6.5

jQuery: Get selected element tag name

jQuery 1.6+

jQuery('selector').prop("tagName").toLowerCase()

Older versions

jQuery('selector').attr("tagName").toLowerCase()

toLowerCase() is not mandatory.

How to store Node.js deployment settings/configuration files?

I will create a folder as config a file naming as config.js and later I will use this file wherever required as below

Example of config.js

module.exports = {
    proxyURL: 'http://url:port',
    TWITTER: {
        consumerkey: 'yourconsumerkey',
        consumerSecrete: 'yourconsumersecrete'
    },
    GOOGLE: {
        consumerkey: 'yourconsumerkey',
        consumerSecrete: 'yourconsumersecrete'
    },
    FACEBOOK: {
        consumerkey: 'yourconsumerkey',
        consumerSecrete: 'yourconsumersecrete'
    }
}

Then if i want to use this config file somewhere

I will first import as below

var config = require('./config');

and I can access the values as below

const oauth = OAuth({
    consumer: {
        key: config.TWITTER.consumerkey,
        secret: config.TWITTER.consumerSecrete
    },
    signature_method: 'HMAC-SHA1',
    hash_function(base_string, key) {
        return crypto.createHmac('sha1', key).update(base_string).digest('base64');
    }
});

How to printf a 64-bit integer as hex?

The warning from your compiler is telling you that your format specifier doesn't match the data type you're passing to it.

Try using %lx or %llx. For more portability, include inttypes.h and use the PRIx64 macro.

For example: printf("val = 0x%" PRIx64 "\n", val); (note that it's string concatenation)

Easy way to export multiple data.frame to multiple Excel worksheets

There's a new library in town, from rOpenSci: writexl

Portable, light-weight data frame to xlsx exporter based on libxlsxwriter. No Java or Excel required

I found it better and faster than the above suggestions (working with the dev version):

library(writexl)
sheets <- list("sheet1Name" = sheet1, "sheet2Name" = sheet2) #assume sheet1 and sheet2 are data frames
write_xlsx(sheets, "path/to/location")

mvn clean install vs. deploy vs. release

The clean, install and deploy phases are valid lifecycle phases and invoking them will trigger all the phases preceding them, and the goals bound to these phases.

mvn clean install

This command invokes the clean phase and then the install phase sequentially:

  • clean: removes files generated at build-time in a project's directory (target by default)
  • install: installs the package into the local repository, for use as a dependency in other projects locally.

mvn deploy

This command invokes the deploy phase:

  • deploy: copies the final package to the remote repository for sharing with other developers and projects.

mvn release

This is not a valid phase nor a goal so this won't do anything. But if refers to the Maven Release Plugin that is used to automate release management. Releasing a project is done in two steps: prepare and perform. As documented:

Preparing a release goes through the following release phases:

  • Check that there are no uncommitted changes in the sources
  • Check that there are no SNAPSHOT dependencies
  • Change the version in the POMs from x-SNAPSHOT to a new version (you will be prompted for the versions to use)
  • Transform the SCM information in the POM to include the final destination of the tag
  • Run the project tests against the modified POMs to confirm everything is in working order
  • Commit the modified POMs
  • Tag the code in the SCM with a version name (this will be prompted for)
  • Bump the version in the POMs to a new value y-SNAPSHOT (these values will also be prompted for)
  • Commit the modified POMs

And then:

Performing a release runs the following release phases:

  • Checkout from an SCM URL with optional tag
  • Run the predefined Maven goals to release the project (by default, deploy site-deploy)

See also

What are public, private and protected in object oriented programming?

To sum it up,in object oriented programming, everything is modeled into classes and objects. Classes contain properties and methods. Public, private and protected keywords are used to specify access to these members(properties and methods) of a class from other classes or other .dlls or even other applications.

Find control by name from Windows Forms controls

TextBox tbx = this.Controls.Find("textBox1", true).FirstOrDefault() as TextBox;
tbx.Text = "found!";

If Controls.Find is not found "textBox1" => error. You must add code.

If(tbx != null)

Edit:

TextBox tbx = this.Controls.Find("textBox1", true).FirstOrDefault() as TextBox;
If(tbx != null)
   tbx.Text = "found!";

How to assign text size in sp value using java code

This is code for the convert PX to SP format. 100% Works

view.setTextSize(TypedValue.COMPLEX_UNIT_PX, 24);

How do I use jQuery to redirect?

You forgot the HTTP part:

window.location.href = "http://example.com/Registration/Success/";

"Uncaught TypeError: undefined is not a function" - Beginner Backbone.js Application

I have occurred the same error look following example-

async.waterfall([function(waterCB) {
    waterCB(null);
}, function(**inputArray**, waterCB) {
    waterCB(null);
}], function(waterErr, waterResult) {
    console.log('Done');
});

In the above waterfall function, I am accepting inputArray parameter in waterfall 2nd function. But this inputArray not passed in waterfall 1st function in waterCB.

Cheak your function parameters Below are a correct example.

async.waterfall([function(waterCB) {
    waterCB(null, **inputArray**);
}, function(**inputArray**, waterCB) {
    waterCB(null);
}], function(waterErr, waterResult) {
    console.log('Done');
});

Thanks

Can’t delete docker image with dependent child images

Here's a script to remove an image and all the images that depend on it.

#!/bin/bash

if [[ $# -lt 1 ]]; then
    echo must supply image to remove;
    exit 1;
fi;

get_image_children ()
{
    ret=()
    for i in $(docker image ls -a --no-trunc -q); do
        #>&2 echo processing image "$i";
        #>&2 echo parent is $(docker image inspect --format '{{.Parent}}' "$i")
        if [[ "$(docker image inspect --format '{{.Parent}}' "$i")" == "$1" ]]; then
            ret+=("$i");
        fi;
    done;
    echo "${ret[@]}";
}

realid=$(docker image inspect --format '{{.Id}}' "$1")
if [[ -z "$realid" ]]; then
    echo "$1 is not a valid image.";
    exit 2;
fi;
images_to_remove=("$realid");
images_to_process=("$realid");
while [[ "${#images_to_process[@]}" -gt 0 ]]; do
    children_to_process=();
    for i in "${!images_to_process[@]}"; do
        children=$(get_image_children "${images_to_process[$i]}");
        if [[ ! -z "$children" ]]; then
            # allow word splitting on the children.
            children_to_process+=($children);
        fi;
    done;
    if [[ "${#children_to_process[@]}" -gt 0 ]]; then
        images_to_process=("${children_to_process[@]}");
        images_to_remove+=("${children_to_process[@]}");
    else
        #no images have any children. We're done creating the graph.
        break;
    fi;
done;
echo images_to_remove = "$(printf %s\n "${images_to_remove[@]}")";
indices=(${!images_to_remove[@]});
for ((i="${#indices[@]}" - 1; i >= 0; --i)) ; do
    image_to_remove="${images_to_remove[indices[i]]}"
    if [[ "${image_to_remove:0:7}" == "sha256:" ]]; then
        image_to_remove="${image_to_remove:7}";
    fi
    echo removing image "$image_to_remove";
    docker rmi "$image_to_remove";
done

Verifying a specific parameter with Moq

Had one of these as well, but the parameter of the action was an interface with no public properties. Ended up using It.Is() with a seperate method and within this method had to do some mocking of the interface

public interface IQuery
{
    IQuery SetSomeFields(string info);
}

void DoSomeQuerying(Action<IQuery> queryThing);

mockedObject.Setup(m => m.DoSomeQuerying(It.Is<Action<IQuery>>(q => MyCheckingMethod(q)));

private bool MyCheckingMethod(Action<IQuery> queryAction)
{
    var mockQuery = new Mock<IQuery>();
    mockQuery.Setup(m => m.SetSomeFields(It.Is<string>(s => s.MeetsSomeCondition())
    queryAction.Invoke(mockQuery.Object);
    mockQuery.Verify(m => m.SetSomeFields(It.Is<string>(s => s.MeetsSomeCondition(), Times.Once)
    return true
}

Setting top and left CSS attributes

We can create a new CSS class for div.

 .div {
      position: absolute;
      left: 150px;
      width: 200px;
      height: 120px;
    }

How to suppress binary file matching results in grep

There are three options, that you can use. -I is to exclude binary files in grep. Other are for line numbers and file names.

grep -I -n -H 


-I -- process a binary file as if it did not contain matching data; 
-n -- prefix each line of output with the 1-based line number within its input file
-H -- print the file name for each match

So this might be a way to run grep:

grep -InH your-word *

Calculate rolling / moving average in C++

You could implement a ring buffer. Make an array of 1000 elements, and some fields to store the start and end indexes and total size. Then just store the last 1000 elements in the ring buffer, and recalculate the average as needed.

Setting and getting localStorage with jQuery

You said you are attempting to get the text from a div and store it on local storage.

Please Note: Text and Html are different. In the question you mentioned text. html() will return Html content like <a>example</a>. if you want to get Text content then you have to use text() instead of html() then the result will be example instead of <a>example<a>. Anyway, I am using your terminology let it be Text.

Step 1: get the text from div.

what you did is not get the text from div but set the text to a div.

$('#test').html("Test"); 

is actually setting text to div and the output will be a jQuery object. That is why it sets it as [object Object].

To get the text you have to write like this
$('#test').html();

This will return a string not an object so the result will be Test in your case.

Step 2: set it to local storage.

Your approach is correct and you can write it as

localStorage.key=value

But the preferred approach is

localStorage.setItem(key,value); to set

localStorage.getItem(key); to get.

key and value must be strings.

so in your context code will become

$('#test').html("Test");
localStorage.content = $('#test').html();
$('#test').html(localStorage.content);

But I don't find any meaning in your code. Because you want to get the text from div and store it on local storage. And again you are reading the same from local storage and set to div. just like a=10; b=a; a=b;

If you are facing any other problems please update your question accordingly.

How can I render Partial views in asp.net mvc 3?

<%= Html.Partial("PartialName", Model) %>

anaconda - graphviz - can't import after installation

Graphviz is evidently included in Anaconda so as to be used with pydot or pydot-ng (both of which are included in Anaconda). You may want to consider using one of those instead of the 'graphviz' Python module.

Calling Scalar-valued Functions in SQL

Make sure you have the correct database selected. You may have the master database selected if you are trying to run it in a new query window.

How to find and return a duplicate value in array

Ruby Array objects have a great method, select.

select {|item| block } ? new_ary
select ? an_enumerator

The first form is what interests you here. It allows you to select objects which pass a test.

Ruby Array objects have another method, count.

count ? int
count(obj) ? int
count { |item| block } ? int

In this case, you are interested in duplicates (objects which appear more than once in the array). The appropriate test is a.count(obj) > 1.

If a = ["A", "B", "C", "B", "A"], then

a.select{|item| a.count(item) > 1}.uniq
=> ["A", "B"]

You state that you only want one object. So pick one.

Find which commit is currently checked out in Git

If you want to extract just a simple piece of information, you can get that using git show with the --format=<string> option...and ask it not to give you the diff with --no-patch. This means you can get a printf-style output of whatever you want, which might often be a single field.

For instance, to get just the shortened hash (%h) you could say:

$ git show --format="%h" --no-patch
4b703eb

If you're looking to save that into an environment variable in bash (a likely thing for people to want to do) you can use the $() syntax:

$ GIT_COMMIT="$(git show --format="%h" --no-patch)"

$ echo $GIT_COMMIT
4b703eb

The full list of what you can do is in git show --help. But here's an abbreviated list of properties that might be useful:

  • %H commit hash
  • %h abbreviated commit hash
  • %T tree hash
  • %t abbreviated tree hash
  • %P parent hashes
  • %p abbreviated parent hashes
  • %an author name
  • %ae author email
  • %at author date, UNIX timestamp
  • %aI author date, strict ISO 8601 format
  • %cn committer name
  • %ce committer email
  • %ct committer date, UNIX timestamp
  • %cI committer date, strict ISO 8601 format
  • %s subject
  • %f sanitized subject line, suitable for a filename
  • %gD reflog selector, e.g., refs/stash@{1}
  • %gd shortened reflog selector, e.g., stash@{1}

How to wrap text in textview in Android

Use app:breakStrategy="simple" in AppCompatTextView, it will control over paragraph layout.

It has three constant values

  • balanced
  • high_quality
  • simple

Designing in your TextView xml

<android.support.v7.widget.AppCompatTextView
        android:id="@+id/textquestion"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:gravity="center"
        android:scrollHorizontally="false"
        android:text="Your Question Display Hear....Your Question Display Hear....Your Question Display Hear....Your Question Display Hear...."
        android:textColor="@android:color/black"
        android:textSize="20sp"
        android:textStyle="bold"
        app:breakStrategy="simple" />

If your current minimum api level is 23 or more then in Coding

yourtextview.setBreakStrategy(Layout.BREAK_STRATEGY_SIMPLE);

For more refrence refer this BreakStrategy

Textview breakStrategy image

How to open .dll files to see what is written inside?

you are better off with a decompiler like redgates .net reflector or jetbrains resharper decompiler. there are open source ones also like

http://www.jetbrains.com/decompiler/

http://ilspy.net/

How to randomly pick an element from an array

You can also use

public static int getRandom(int[] array) {
    int rnd = (int)(Math.random()*array.length);
    return array[rnd];
}

Math.random() returns an double between 0.0 (inclusive) to 1.0 (exclusive)

Multiplying this with array.length gives you a double between 0.0 (inclusive) and array.length (exclusive)

Casting to int will round down giving you and integer between 0 (inclusive) and array.length-1 (inclusive)

How to use "Share image using" sharing Intent to share images in android?

Strring temp="facebook",temp="whatsapp",temp="instagram",temp="googleplus",temp="share";

    if(temp.equals("facebook"))
    {
        Intent intent = getPackageManager().getLaunchIntentForPackage("com.facebook.katana");
        if (intent != null) {

            Intent shareIntent = new Intent(android.content.Intent.ACTION_SEND);
            shareIntent.setType("image/png");
            shareIntent.putExtra(Intent.EXTRA_STREAM, Uri.parse("file://" + "/sdcard/folder name/abc.png"));
            shareIntent.setFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
            shareIntent.setPackage("com.facebook.katana");
            startActivity(shareIntent);

        }
        else
        {
            Toast.makeText(MainActivity.this, "Facebook require..!!", Toast.LENGTH_SHORT).show();
        }
    }
    if(temp.equals("whatsapp"))
    {

        try {
            File filePath = new File("/sdcard/folder name/abc.png");
            final ComponentName name = new ComponentName("com.whatsapp", "com.whatsapp.ContactPicker");
            Intent oShareIntent = new Intent();
            oShareIntent.setComponent(name);
            oShareIntent.setType("text/plain");
            oShareIntent.putExtra(android.content.Intent.EXTRA_TEXT, "Website : www.google.com");
            oShareIntent.putExtra(Intent.EXTRA_STREAM, Uri.fromFile(filePath));
            oShareIntent.setType("image/jpeg");
            oShareIntent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
            MainActivity.this.startActivity(oShareIntent);


        } catch (Exception e) {
            Toast.makeText(MainActivity.this, "WhatsApp require..!!", Toast.LENGTH_SHORT).show();
        }
    }
    if(temp.equals("instagram"))
    {
        Intent intent = getPackageManager().getLaunchIntentForPackage("com.instagram.android");
        if (intent != null)
        {
            File filePath =new File("/sdcard/folder name/"abc.png");
            Intent shareIntent = new Intent(android.content.Intent.ACTION_SEND);
            shareIntent.setType("image");
            shareIntent.putExtra(Intent.EXTRA_STREAM, Uri.parse("file://" + "/sdcard/Chitranagari/abc.png"));
            shareIntent.setPackage("com.instagram.android");
            startActivity(shareIntent);

        }
        else
        {
            Toast.makeText(MainActivity.this, "Instagram require..!!", Toast.LENGTH_SHORT).show();

        }
    }
    if(temp.equals("googleplus"))
    {

        try
        {

            Calendar c = Calendar.getInstance();
            SimpleDateFormat sdf = new SimpleDateFormat("dd-MM-yyyy hh:mm:ss");
            String strDate = sdf.format(c.getTime());
            Intent shareIntent = ShareCompat.IntentBuilder.from(MainActivity.this).getIntent();
            shareIntent.setType("text/plain");
            shareIntent.putExtra(Intent.EXTRA_TEXT, "Website : www.google.com");
            shareIntent.putExtra(Intent.EXTRA_STREAM, Uri.parse("file://" + "/sdcard/folder name/abc.png"));
            shareIntent.setPackage("com.google.android.apps.plus");
            shareIntent.setAction(Intent.ACTION_SEND);
            startActivity(shareIntent);
        }catch (Exception e)
        {
            e.printStackTrace();
            Toast.makeText(MainActivity.this, "Googleplus require..!!", Toast.LENGTH_SHORT).show();
        }
    }
    if(temp.equals("share")) {

        File filePath =new File("/sdcard/folder name/abc.png");  //optional //internal storage
        Intent shareIntent = new Intent();
        shareIntent.setAction(Intent.ACTION_SEND);
        shareIntent.putExtra(Intent.EXTRA_TEXT, "Website : www.google.com");
        shareIntent.putExtra(Intent.EXTRA_STREAM, Uri.fromFile(filePath));  //optional//use this when you want to send an image
        shareIntent.setType("image/jpeg");
        shareIntent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
        startActivity(Intent.createChooser(shareIntent, "send"));

    }

What's the easiest way to install a missing Perl module?

Many times it does happen that cpan install command fails with the message like "make test had returned bad status, won't install without force"

In that case following is the way to install the module:

perl -MCPAN -e "CPAN::Shell->force(qw(install Foo::Bar));"

How do you convert a DataTable into a generic list?

If anyone want's to create custom function to convert datatable to list

class Program
{
    static void Main(string[] args)
    {
        DataTable table = GetDataTable();
        var sw = new Stopwatch();

        sw.Start();
        LinqMethod(table);
        sw.Stop();
        Console.WriteLine("Elapsed time for Linq Method={0}", sw.ElapsedMilliseconds);

        sw.Reset();

        sw.Start();
        ForEachMethod(table);
        sw.Stop();
        Console.WriteLine("Elapsed time for Foreach method={0}", sw.ElapsedMilliseconds);

        Console.ReadKey();
    }

    private static DataTable GetDataTable()
    {
        var table = new DataTable();
        table.Columns.Add("ID", typeof(double));
        table.Columns.Add("CategoryName", typeof(string));
        table.Columns.Add("Active", typeof(double));

        var rand = new Random();

        for (int i = 0; i < 100000; i++)
        {
            table.Rows.Add(i, "name" + i,  rand.Next(0, 2));
        }
        return table;
    }

    private static void LinqMethod(DataTable table)
    {
        var list = table.AsEnumerable()
            .Skip(1)
            .Select(dr =>
                new Category
                {
                    Id = Convert.ToInt32(dr.Field<double>("ID")),
                    CategoryName = dr.Field<string>("CategoryName"),                      
                    IsActive =
                            dr.Field<double>("Active") == 1 ? true : false
                }).ToList();
    }
    private static void ForEachMethod(DataTable table)
    {
        var categoryList = new List<Category>(table.Rows.Count);
        foreach (DataRow row in table.Rows)
        {
            var values = row.ItemArray;
            var category = new Category()
            {
                Id = Convert.ToInt32(values[0]),
                CategoryName = Convert.ToString(values[1]),                   
                IsActive = (double)values[2] == 1 ? true : false
            };
            categoryList.Add(category);
        }
    }

    private class Category
    {
        public int Id { get; set; }
        public string CategoryName { get; set; }
        public bool IsActive { get; set; }
    }
}

If we execute above code, Foreach method finishes in 56ms while linq one takes 101ms ( for 1000 records). So Foreach method is better to use. Source:Ways to Convert Datatable to List in C# (with performance test example)

Java program to connect to Sql Server and running the sample query From Eclipse

The link has the driver for sqlserver, download and add it your eclipse buildpath.

Cannot set property 'display' of undefined

document.getElementsByClassName('btn-pageMenu') delivers a nodeList. You should use: document.getElementsByClassName('btn-pageMenu')[0].style.display (if it's the first element from that list you want to change.

If you want to change style.display for all nodes loop through the list:

var elems = document.getElementsByClassName('btn-pageMenu');
for (var i=0;i<elems.length;i+=1){
  elems[i].style.display = 'block';
}

to be complete: if you use jquery it is as simple as:

?$('.btn-pageMenu').css('display'???????????????????????????,'block');??????

Check file extension in upload form in PHP

Not sure if this would have a faster computational time, but another option...

$acceptedFormats = array('gif', 'png', 'jpg');

if(!in_array(pathinfo($filename, PATHINFO_EXTENSION), $acceptedFormats))) {
    echo 'error';
}

How do I determine the size of an object in Python?

The Pympler package's asizeof module can do this.

Use as follows:

from pympler import asizeof
asizeof.asizeof(my_object)

Unlike sys.getsizeof, it works for your self-created objects. It even works with numpy.

>>> asizeof.asizeof(tuple('bcd'))
200
>>> asizeof.asizeof({'foo': 'bar', 'baz': 'bar'})
400
>>> asizeof.asizeof({})
280
>>> asizeof.asizeof({'foo':'bar'})
360
>>> asizeof.asizeof('foo')
40
>>> asizeof.asizeof(Bar())
352
>>> asizeof.asizeof(Bar().__dict__)
280
>>> A = rand(10)
>>> B = rand(10000)
>>> asizeof.asizeof(A)
176
>>> asizeof.asizeof(B)
80096

As mentioned,

The (byte)code size of objects like classes, functions, methods, modules, etc. can be included by setting option code=True.

And if you need other view on live data, Pympler's

module muppy is used for on-line monitoring of a Python application and module Class Tracker provides off-line analysis of the lifetime of selected Python objects.

convert double to int

Yeah, why not?

double someDouble = 12323.2;
int someInt = (int)someDouble;

Using the Convert class works well too.

int someOtherInt = Convert.ToInt32(someDouble);

How to see JavaDoc in IntelliJ IDEA?

The closest to Eclipse will be Ctrl+Button2 Click (Scroll click)

It's called Quick Doc in IntelliJ, I wish guys from JetBrains one day add quick doc like Eclipse with Ctrl+Mouse Move it's so much better.

In my case only with only mouse move is a bit annoying, so if you search in Preferences/Settings --> Keymap for "quick documentation" you will find:

  • Win-Linux: "Ctrl+Q" and "Ctrl+Button2 Click" (Scroll click)
  • Mac: "Ctrl+J" and "Ctrl+Button2 Click" (Scroll click)

How exactly does the python any() function work?

If you use any(lst) you see that lst is the iterable, which is a list of some items. If it contained [0, False, '', 0.0, [], {}, None] (which all have boolean values of False) then any(lst) would be False. If lst also contained any of the following [-1, True, "X", 0.00001] (all of which evaluate to True) then any(lst) would be True.

In the code you posted, x > 0 for x in lst, this is a different kind of iterable, called a generator expression. Before generator expressions were added to Python, you would have created a list comprehension, which looks very similar, but with surrounding []'s: [x > 0 for x in lst]. From the lst containing [-1, -2, 10, -4, 20], you would get this comprehended list: [False, False, True, False, True]. This internal value would then get passed to the any function, which would return True, since there is at least one True value.

But with generator expressions, Python no longer has to create that internal list of True(s) and False(s), the values will be generated as the any function iterates through the values generated one at a time by the generator expression. And, since any short-circuits, it will stop iterating as soon as it sees the first True value. This would be especially handy if you created lst using something like lst = range(-1,int(1e9)) (or xrange if you are using Python2.x). Even though this expression will generate over a billion entries, any only has to go as far as the third entry when it gets to 1, which evaluates True for x>0, and so any can return True.

If you had created a list comprehension, Python would first have had to create the billion-element list in memory, and then pass that to any. But by using a generator expression, you can have Python's builtin functions like any and all break out early, as soon as a True or False value is seen.

Adding values to a C# array

You can't do this directly. However, you can use Linq to do this:

List<int> termsLst=new List<int>();
for (int runs = 0; runs < 400; runs++)
{
    termsLst.Add(runs);
}
int[] terms = termsLst.ToArray();

If the array terms wasn't empty in the beginning, you can convert it to List first then do your stuf. Like:

    List<int> termsLst = terms.ToList();
    for (int runs = 0; runs < 400; runs++)
    {
        termsLst.Add(runs);
    }
    terms = termsLst.ToArray();

Note: don't miss adding 'using System.Linq;' at the begaining of the file.

How can I strip first and last double quotes?

Starting in Python 3.9, you can use removeprefix and removesuffix:

'"" " " ""\\1" " "" ""'.removeprefix('"').removesuffix('"')
# '" " " ""\\1" " "" "'

How to round the minute of a datetime object

This will get the 'floor' of a datetime object stored in tm rounded to the 10 minute mark before tm.

tm = tm - datetime.timedelta(minutes=tm.minute % 10,
                             seconds=tm.second,
                             microseconds=tm.microsecond)

If you want classic rounding to the nearest 10 minute mark, do this:

discard = datetime.timedelta(minutes=tm.minute % 10,
                             seconds=tm.second,
                             microseconds=tm.microsecond)
tm -= discard
if discard >= datetime.timedelta(minutes=5):
    tm += datetime.timedelta(minutes=10)

or this:

tm += datetime.timedelta(minutes=5)
tm -= datetime.timedelta(minutes=tm.minute % 10,
                         seconds=tm.second,
                         microseconds=tm.microsecond)

How to verify CuDNN installation?

I have cuDNN 8.0 and none of the suggestions above worked for me. The desired information was in /usr/include/cudnn_version.h, so

cat /usr/include/cudnn_version.h | grep CUDNN_MAJOR -A 2

did the trick.

In plain English, what does "git reset" do?

TL;DR

git reset resets Staging to the last commit. Use --hard to also reset files in your Working directory to the last commit.

LONGER VERSION

But that's obviously simplistic hence the many rather verbose answers. It made more sense for me to read up on git reset in the context of undoing changes. E.g. see this:

If git revert is a “safe” way to undo changes, you can think of git reset as the dangerous method. When you undo with git reset(and the commits are no longer referenced by any ref or the reflog), there is no way to retrieve the original copy—it is a permanent undo. Care must be taken when using this tool, as it’s one of the only Git commands that has the potential to lose your work.

From https://www.atlassian.com/git/tutorials/undoing-changes/git-reset

and this

On the commit-level, resetting is a way to move the tip of a branch to a different commit. This can be used to remove commits from the current branch.

From https://www.atlassian.com/git/tutorials/resetting-checking-out-and-reverting/commit-level-operations

What are .NumberFormat Options In Excel VBA?

Thanks to this question (and answers), I discovered an easy way to get at the exact NumberFormat string for virtually any format that Excel has to offer.


How to Obtain the NumberFormat String for Any Excel Number Format


Step 1: In the user interface, set a cell to the NumberFormat you want to use.

I manually formatted a cell to Chinese (PRC) currency

In my example, I selected the Chinese (PRC) Currency from the options contained in the "Account Numbers Format" combo box.

Step 2: Expand the Number Format dropdown and select "More Number Formats...".

Open the Number Format dropdown

Step 3: In the Number tab, in Category, click "Custom".

Click Custom

The "Sample" section shows the Chinese (PRC) currency formatting that I applied.

The "Type" input box contains the NumberFormat string that you can use programmatically.

So, in this example, the NumberFormat of my Chinese (PRC) Currency cell is as follows:

_ [$¥-804]* #,##0.00_ ;_ [$¥-804]* -#,##0.00_ ;_ [$¥-804]* "-"??_ ;_ @_ 

If you do these steps for each NumberFormat that you desire, then the world is yours.

I hope this helps.

How to create a MySQL hierarchical recursive query?

If you need quick read speed, the best option is to use a closure table. A closure table contains a row for each ancestor/descendant pair. So in your example, the closure table would look like

ancestor | descendant | depth
0        | 0          | 0
0        | 19         | 1
0        | 20         | 2
0        | 21         | 3
0        | 22         | 4
19       | 19         | 0
19       | 20         | 1
19       | 21         | 3
19       | 22         | 4
20       | 20         | 0
20       | 21         | 1
20       | 22         | 2
21       | 21         | 0
21       | 22         | 1
22       | 22         | 0

Once you have this table, hierarchical queries become very easy and fast. To get all the descendants of category 20:

SELECT cat.* FROM categories_closure AS cl
INNER JOIN categories AS cat ON cat.id = cl.descendant
WHERE cl.ancestor = 20 AND cl.depth > 0

Of course, there is a big downside whenever you use denormalized data like this. You need to maintain the closure table alongside your categories table. The best way is probably to use triggers, but it is somewhat complex to correctly track inserts/updates/deletes for closure tables. As with anything, you need to look at your requirements and decide what approach is best for you.

Edit: See the question What are the options for storing hierarchical data in a relational database? for more options. There are different optimal solutions for different situations.

`IF` statement with 3 possible answers each based on 3 different ranges

=IF(X2>=85,0.559,IF(X2>=80,0.327,IF(X2>=75,0.255,-1)))

Explanation:

=IF(X2>=85,                  'If the value is in the highest bracket
      0.559,                 'Use the appropriate number
      IF(X2>=80,             'Otherwise, if the number is in the next highest bracket
           0.327,            'Use the appropriate number
           IF(X2>=75,        'Otherwise, if the number is in the next highest bracket
              0.255,         'Use the appropriate number
              -1             'Otherwise, we're not in any of the ranges (Error)
             )
        )
   )

Pass multiple optional parameters to a C# function

1.You can make overload functions.

SomeF(strin s){}   
SomeF(string s, string s2){}    
SomeF(string s1, string s2, string s3){}   

More info: http://csharpindepth.com/Articles/General/Overloading.aspx

2.or you may create one function with params

SomeF( params string[] paramArray){}
SomeF("aa","bb", "cc", "dd", "ff"); // pass as many as you like

More info: https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/keywords/params

3.or you can use simple array

Main(string[] args){}

Git will not init/sync/update new submodules

Just sharing what worked for me:

git clone --recurse-submodules <repository path>

This clones the remote repository already including the submodules. This means you won't need to run git submodule update or init after cloning.

Working with select using AngularJS's ng-options

One thing to note is that ngModel is required for ngOptions to work... note the ng-model="blah" which is saying "set $scope.blah to the selected value".

Try this:

<select ng-model="blah" ng-options="item.ID as item.Title for item in items"></select>

Here's more from AngularJS's documentation (if you haven't seen it):

for array data sources:

  • label for value in array
  • select as label for value in array
  • label group by group for value in array = select as label group by group for value in array

for object data sources:

  • label for (key , value) in object
  • select as label for (key , value) in object
  • label group by group for (key, value) in object
  • select as label group by group for (key, value) in object

For some clarification on option tag values in AngularJS:

When you use ng-options, the values of option tags written out by ng-options will always be the index of the array item the option tag relates to. This is because AngularJS actually allows you to select entire objects with select controls, and not just primitive types. For example:

app.controller('MainCtrl', function($scope) {
   $scope.items = [
     { id: 1, name: 'foo' },
     { id: 2, name: 'bar' },
     { id: 3, name: 'blah' }
   ];
});
<div ng-controller="MainCtrl">
   <select ng-model="selectedItem" ng-options="item as item.name for item in items"></select>
   <pre>{{selectedItem | json}}</pre>
</div>

The above will allow you to select an entire object into $scope.selectedItem directly. The point is, with AngularJS, you don't need to worry about what's in your option tag. Let AngularJS handle that; you should only care about what's in your model in your scope.

Here is a plunker demonstrating the behavior above, and showing the HTML written out


Dealing with the default option:

There are a few things I've failed to mention above relating to the default option.

Selecting the first option and removing the empty option:

You can do this by adding a simple ng-init that sets the model (from ng-model) to the first element in the items your repeating in ng-options:

<select ng-init="foo = foo || items[0]" ng-model="foo" ng-options="item as item.name for item in items"></select>

Note: This could get a little crazy if foo happens to be initialized properly to something "falsy". In that case, you'll want to handle the initialization of foo in your controller, most likely.

Customizing the default option:

This is a little different; here all you need to do is add an option tag as a child of your select, with an empty value attribute, then customize its inner text:

<select ng-model="foo" ng-options="item as item.name for item in items">
   <option value="">Nothing selected</option>
</select>

Note: In this case the "empty" option will stay there even after you select a different option. This isn't the case for the default behavior of selects under AngularJS.

A customized default option that hides after a selection is made:

If you wanted your customized default option to go away after you select a value, you can add an ng-hide attribute to your default option:

<select ng-model="foo" ng-options="item as item.name for item in items">
   <option value="" ng-if="foo">Select something to remove me.</option>
</select>

How to use zIndex in react-native

Use elevation instead of zIndex for android devices

elevatedElement: {
  zIndex: 3, // works on ios
  elevation: 3, // works on android
}

This worked fine for me!

Change New Google Recaptcha (v2) Width

.g-recaptcha{
    -moz-transform:scale(1.1);
    -ms-transform:scale(1.1); 
    -o-transform:scale(1.1); 
    -moz-transform-origin:0; 
    -ms-transform-origin:0;
    -o-transform-origin:0;
    -webkit-transform:scale(1.1);
    transform:scale(1.1);
    -webkit-transform-origin:0 0;
    transform-origin:0;
    filter: progid:DXImageTransform.Microsoft.Matrix(M11=1.1,M12=0,M21=0,M22=1.1,SizingMethod='auto expand');
}

Test file upload using HTTP PUT method

In my opinion the best tool for such testing is curl. Its --upload-file option uploads a file by PUT, which is exactly what you want (and it can do much more, like modifying HTTP headers, in case you need it):

curl http://myservice --upload-file file.txt

Exit codes in Python

You're looking for calls to sys.exit() in the script. The argument to that method is returned to the environment as the exit code.

It's fairly likely that the script is never calling the exit method, and that 0 is the default exit code.

JQuery: How to get selected radio button value?

For radio buttons use the following script:

var myRadio = $('input[name=meme_wall_share]');
var checkedValue = myRadio.filter(':checked').val();

Why is String immutable in Java?

From the Security point of view we can use this practical example:

DBCursor makeConnection(String IP,String PORT,String USER,String PASS,String TABLE) {

    // if strings were mutable IP,PORT,USER,PASS can be changed by validate function
    Boolean validated = validate(IP,PORT,USER,PASS);

    // here we are not sure if IP, PORT, USER, PASS changed or not ??
    if (validated) {
         DBConnection conn = doConnection(IP,PORT,USER,PASS);
    }

    // rest of the code goes here ....
}

Java, Simplified check if int array contains int

Guava offers additional methods for primitive types. Among them a contains method which takes the same arguments as yours.

public boolean contains(final int[] array, final int key) {
    return Ints.contains(array, key);
}

You might as well statically import the guava version.

See Guava Primitives Explained

Adding parameter to ng-click function inside ng-repeat doesn't seem to work

this works. thanks. I am injecting custom html and compile it using angular in the controller.

        var tableContent= '<div>Search: <input ng-model="searchText"></div>' 
                            +'<div class="table-heading">'
                            +    '<div class="table-col">Customer ID</div>'
                           + ' <div class="table-col" ng-click="vm.openDialog(c.CustomerId)">{{c.CustomerId}}</div>';

            $timeout(function () {
            var linkingFunction = $compile(tableContent);
            var elem = linkingFunction($scope);

            // You can then use the DOM element like normal.
            jQuery(tablePanel).append(elem);

            console.log("timeout");
        },100);

Best way to store date/time in mongodb

One datestamp is already in the _id object, representing insert time

So if the insert time is what you need, it's already there:

Login to mongodb shell

ubuntu@ip-10-0-1-223:~$ mongo 10.0.1.223
MongoDB shell version: 2.4.9
connecting to: 10.0.1.223/test

Create your database by inserting items

> db.penguins.insert({"penguin": "skipper"})
> db.penguins.insert({"penguin": "kowalski"})
> 

Lets make that database the one we are on now

> use penguins
switched to db penguins

Get the rows back:

> db.penguins.find()
{ "_id" : ObjectId("5498da1bf83a61f58ef6c6d5"), "penguin" : "skipper" }
{ "_id" : ObjectId("5498da28f83a61f58ef6c6d6"), "penguin" : "kowalski" }

Get each row in yyyy-MM-dd HH:mm:ss format:

> db.penguins.find().forEach(function (doc){ d = doc._id.getTimestamp(); print(d.getFullYear()+"-"+(d.getMonth()+1)+"-"+d.getDate() + " " + d.getHours() + ":" + d.getMinutes() + ":" + d.getSeconds()) })
2014-12-23 3:4:41
2014-12-23 3:4:53

If that last one-liner confuses you I have a walkthrough on how that works here: https://stackoverflow.com/a/27613766/445131

How to convert a Drawable to a Bitmap?

A Drawable can be drawn onto a Canvas, and a Canvas can be backed by a Bitmap:

(Updated to handle a quick conversion for BitmapDrawables and to ensure that the Bitmap created has a valid size)

public static Bitmap drawableToBitmap (Drawable drawable) {
    if (drawable instanceof BitmapDrawable) {
        return ((BitmapDrawable)drawable).getBitmap();
    }

    int width = drawable.getIntrinsicWidth();
    width = width > 0 ? width : 1;
    int height = drawable.getIntrinsicHeight();
    height = height > 0 ? height : 1;

    Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
    Canvas canvas = new Canvas(bitmap); 
    drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());
    drawable.draw(canvas);

    return bitmap;
}

HTTP Status 405 - HTTP method POST is not supported by this URL java servlet

If you're still facing the issue even after replacing doGet() with doPost() and changing the form method="post". Try clearing the cache of the browser or hit the URL in another browser or incognito/private mode. It may works!

For best practices, please follow this link. https://www.oracle.com/technetwork/articles/javase/servlets-jsp-140445.html

What algorithms compute directions from point A to point B on a map?

I see what's up with the maps in the OP:

Look at the route with the intermediate point specified: The route goes slightly backwards due to that road that isn't straight.

If their algorithm won't backtrack it won't see the shorter route.

Debugging "Element is not clickable at point" error

I was facing the same problem with clj-webdriver (clojure port of Selenium). I just translated the previous solution to clojure for convenience. You can call this function before doing click or whatever to avoid that problem.

(defn scrollTo
  "Scrolls to the position of the given css selector if found"
  [q]
  (if (exists? q) 
    (let [ loc (location-once-visible q) jscript (str "window.scrollTo(" (:x loc) "," (:y loc) ")") ] 
      (execute-script jscript))))

Filter object properties by key in ES6

OK, how about this:

const myData = {
  item1: { key: 'sdfd', value:'sdfd' },
  item2: { key: 'sdfd', value:'sdfd' },
  item3: { key: 'sdfd', value:'sdfd' }
};

function filteredObject(obj, filter) {
  if(!Array.isArray(filter)) {
   filter = [filter.toString()];
  }
  const newObj = {};
  for(i in obj) {
    if(!filter.includes(i)) {
      newObj[i] = obj[i];
    }
  }
  return newObj;
}

and call it like this:

filteredObject(myData, ['item2']); //{item1: { key: 'sdfd', value:'sdfd' }, item3: { key: 'sdfd', value:'sdfd' }}

Correct way to detach from a container without stopping it

You can use the --detach-keys option when you run docker attach to override the default CTRL+P, CTRL + Q sequence (that doesn't always work).

For example, when you run docker attach --detach-keys="ctrl-a" test and you press CTRL+A you will exit the container, without killing it.

Other examples:

  • docker attach --detach-keys="ctrl-a,x" test - press CTRL+A and then X to exit
  • docker attach --detach-keys="a,b,c" test - press A, then B, then C to exit

Extract from the official documentation:

If you want, you can configure an override the Docker key sequence for detach. This is useful if the Docker default sequence conflicts with key sequence you use for other applications. There are two ways to define your own detach key sequence, as a per-container override or as a configuration property on your entire configuration.

To override the sequence for an individual container, use the --detach-keys="<sequence>" flag with the docker attach command. The format of the <sequence> is either a letter [a-Z], or the ctrl- combined with any of the following:

  • a-z (a single lowercase alpha character )
  • @ (at sign)
  • [ (left bracket)
  • \ (two backward slashes)
  • _ (underscore)
  • ^ (caret)

These a, ctrl-a, X, or ctrl-\\ values are all examples of valid key sequences. To configure a different configuration default key sequence for all containers, see Configuration file section.

Note: This works since docker version 1.10+ (at the time of this answer, the current version is 18.03)

Fetch API with Cookie

Fetch does not use cookie by default. To enable cookie, do this:

fetch(url, {
  credentials: "same-origin"
}).then(...).catch(...);

How do I check for vowels in JavaScript?

I created a simplified version using Array.prototype.includes(). My technique is similar to @Kunle Babatunde.

_x000D_
_x000D_
const isVowel = (char) => ["a", "e", "i", "o", "u"].includes(char);_x000D_
_x000D_
console.log(isVowel("o"), isVowel("s"));
_x000D_
_x000D_
_x000D_

Excel VBA date formats

Thanks for the input. I'm obviously seeing some issues that aren't being replicated on others machines. Based on Jean's answer I have come up with less elegant solution that seems to work.

Since if I pass the cell a value directly from cdate, or just format it as a number it leaves the cell value as a string I've had to pass the date value into a numerical variable before passing that number back to the cell.

Function CellContentCanBeInterpretedAsADate(cell As Range) As Boolean
    Dim d As Date
    On Error Resume Next
    d = CDate(cell.Value)
    If Err.Number <> 0 Then
        CellContentCanBeInterpretedAsADate = False
    Else
        CellContentCanBeInterpretedAsADate = True
    End If
    On Error GoTo 0
End Function

Example usage:

Dim cell As Range
dim cvalue as double
Set cell = Range("A1")

If CellContentCanBeInterpretedAsADate(cell) Then
    cvalue = cdate(cell.value)
    cell.value = cvalue
    cell.NumberFormat = "mm/dd/yyyy hh:mm"
Else
    cell.NumberFormat = "General"
End If

Gem Command not found

I had the same problem. What I did was:

sudo apt-get update

And then reinstall ruby-full

sudo apt-get install ruby-full

How to change font size in Eclipse for Java text editors?

The Eclipse-Fonts extension will add toolbar buttons and keyboard shortcuts for changing font size. You can then use AutoHotkey to make Ctrl + mousewheel zoom.

Under menu Help ? Install New Software... in the menu, paste the update URL (http://eclipse-fonts.googlecode.com/svn/trunk/FontsUpdate/) into the Works with: text box and press Enter. Expand the tree and select FontsFeature as in the following image:

Eclipse extension installation screen capture

Complete the installation and restart Eclipse. Then you should see the A toolbar buttons (circled in red in the following image) and be able to use the keyboard shortcuts Ctrl + - and Ctrl + = to zoom (although you may have to unbind those keys from Eclipse first).

Eclipse screen capture with the font size toolbar buttons circled

To get Ctrl + mouse wheel zooming, you can use AutoHotkey with the following script:

; Ctrl + mouse wheel zooming in Eclipse.
; Requires Eclipse-Fonts (https://code.google.com/p/eclipse-fonts/).
; Thank you for the unique window class, SWT/Eclipse.
;
#IfWinActive ahk_class SWT_Window0
    ^WheelUp:: Send ^{=}
    ^WheelDown:: Send ^-
#IfWinActive

Setting format and value in input type="date"

Please check this https://stackoverflow.com/a/9519493/1074944 and try this way also $('input[type="date"]').datepicker().prop('type','text'); check the demo

Get column value length, not column max length of value

LENGTH() does return the string length (just verified). I suppose that your data is padded with blanks - try

SELECT typ, LENGTH(TRIM(t1.typ))
FROM AUTA_VIEW t1;

instead.

As OraNob mentioned, another cause could be that CHAR is used in which case LENGTH() would also return the column width, not the string length. However, the TRIM() approach also works in this case.

How to convert .crt to .pem

I found the OpenSSL answer given above didn't work for me, but the following did, working with a CRT file sourced from windows.

openssl x509 -inform DER -in yourdownloaded.crt -out outcert.pem -text

Can iterators be reset in Python?

Return a newly created iterator at the last iteration during the 'iter()' call

class ResetIter: 
  def __init__(self, num):
    self.num = num
    self.i = -1

  def __iter__(self):
    if self.i == self.num-1: # here, return the new object
      return self.__class__(self.num) 
    return self

  def __next__(self):
    if self.i == self.num-1:
      raise StopIteration

    if self.i <= self.num-1:
      self.i += 1
      return self.i


reset_iter = ResetRange(10)
for i in reset_iter:
  print(i, end=' ')
print()

for i in reset_iter:
  print(i, end=' ')
print()

for i in reset_iter:
  print(i, end=' ')

Output:

0 1 2 3 4 5 6 7 8 9 
0 1 2 3 4 5 6 7 8 9 
0 1 2 3 4 5 6 7 8 9 

This version of Android Studio cannot open this project, please retry with Android Studio 3.4 or newer

Try to edit your project build.gradle file and set the android build gradle plugin to classpath 'com.android.tools.build:gradle:3.2.1' within the dependency section.

How to fix broken paste clipboard in VNC on Windows

You likely need to re-start VNC on both ends. i.e. when you say "restarted VNC", you probably just mean the client. But what about the other end? You likely need to re-start that end too. The root cause is likely a conflict. Many apps spy on the clipboard when they shouldn't. And many apps are not forgiving when they go to open the clipboard and can't. Robust ones will retry, others will simply not anticipate a failure and then they get fouled up and need to be restarted. Could be VNC, or it could be another app that's "listening" to the clipboard viewer chain, where it is obligated to pass along notifications to the other apps in the chain. If the notifications aren't sent, then VNC may not even know that there has been a clipboard update.

How to write to a file in Scala?

Giving another answer, because my edits of other answers where rejected.

This is the most concise and simple answer (similar to Garret Hall's)

File("filename").writeAll("hello world")

This is similar to Jus12, but without the verbosity and with correct code style

def using[A <: {def close(): Unit}, B](resource: A)(f: A => B): B =
  try f(resource) finally resource.close()

def writeToFile(path: String, data: String): Unit = 
  using(new FileWriter(path))(_.write(data))

def appendToFile(path: String, data: String): Unit =
  using(new PrintWriter(new FileWriter(path, true)))(_.println(data))

Note you do NOT need the curly braces for try finally, nor lambdas, and note usage of placeholder syntax. Also note better naming.

What is a "bundle" in an Android application

Bundles can be used to send arbitrary data from one activity to another by way of Intents. When you broadcast an Intent, interested Activities (and other BroadcastRecievers) will be notified of this. An intent can contain a Bundle so that you can send extra data along with the Intent.

Bundles are key-value mappings, so in a way they are like a Hash, but they are not strictly limited to a single String / Foo object mapping. Note that only certain data types are considered "Parcelable" and they are explicitly spelled out in the Bundle API.

How to pass password automatically for rsync SSH command?

Following the idea posted by Andrew Seaford, this is done using sshfs:

echo "SuperHardToGuessPass:P" | sshfs -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no [email protected]:/mypath/ /mnt/source-tmp/ -o workaround=rename -o password_stdin
rsync -a /mnt/source-tmp/ /media/destination/
umount /mnt/source-tmp

Changing the sign of a number in PHP?

I think Gumbo's answer is just fine. Some people prefer this fancy expression that does the same thing:

$int = (($int > 0) ? -$int : $int);

EDIT: Apparently you are looking for a function that will make negatives positive as well. I think these answers are the simplest:

/* I am not proposing you actually use functions called
   "makeNegative" and "makePositive"; I am just presenting
   the most direct solution in the form of two clearly named
   functions. */
function makeNegative($num) { return -abs($num); }
function makePositive($num) { return abs($num); }

how to get date of yesterday using php?

there you go

date('d.m.Y',strtotime("-1 days"));

this will work also if month change

How can I trim beginning and ending double quotes from a string?

Modifying @brcolow's answer a bit

if (string != null && string.length() >= 2 && string.startsWith("\"") && string.endsWith("\"") {
    string = string.substring(1, string.length() - 1);
}

Binding IIS Express to an IP Address

Below are the complete changes I needed to make to run my x64 bit IIS application using IIS Express, so that it was accessible to a remote host:

iisexpress /config:"C:\Users\test-user\Documents\IISExpress\config\applicationhost.config" /site:MyWebSite
Starting IIS Express ...
Successfully registered URL "http://192.168.2.133:8080/" for site "MyWebSite" application "/"
Registration completed for site "MyWebSite"
IIS Express is running.
Enter 'Q' to stop IIS Express

The configuration file (applicationhost.config) had a section added as follows:

<sites>
  <site name="MyWebsite" id="2">
    <application path="/" applicationPool="Clr4IntegratedAppPool">
      <virtualDirectory path="/" physicalPath="C:\build\trunk\MyWebsite" />
    </application>
    <bindings>
      <binding protocol="http" bindingInformation=":8080:192.168.2.133" />
    </bindings>
  </site>

The 64 bit version of the .NET framework can be enabled as follows:

<globalModules>
    <!--
        <add name="ManagedEngine" image="%windir%\Microsoft.NET\Framework\v2.0.50727\webengine.dll" preCondition="integratedMode,runtimeVersionv2.0,bitness32" />
        <add name="ManagedEngineV4.0_32bit" image="%windir%\Microsoft.NET\Framework\v4.0.30319\webengine4.dll" preCondition="integratedMode,runtimeVersionv4.0,bitness32" />
    -->             
    <add name="ManagedEngine64" image="%windir%\Microsoft.NET\Framework64\v4.0.30319\webengine4.dll" preCondition="integratedMode,runtimeVersionv4.0,bitness64" />

I get conflicting provisioning settings error when I try to archive to submit an iOS app

Try either of the following

1.Removing and adding ios platform and rebuild the project for ios

ionic cordova platform rm ios
ionic cordova platform add ios
ionic cordova build ios --release

2.Changing the Xcode Build Setting

The solution was to uncheck it, then check it again and reselect the Team. Xcode then fixed whatever was causing the issue on its own.

3.Change the following code in platform

This didn’t make any sense to me, since I had set the project to auto sign in xcode. Like you, the check and uncheck didn’t work. But then I read the last file path given and followed it. The file path is APP > Platforms > ios > Cordova > build-release.xconfig

And in the file, iPhone Distribution is explicitly set for CODE_SIGN_IDENTITY.

Change:

CODE_SIGN_IDENTITY = iPhone Distribution
CODE_SIGN_IDENTITY[sdk=iphoneos*] = iPhone Distribution

To:

CODE_SIGN_IDENTITY = iPhone Developer
CODE_SIGN_IDENTITY[sdk=iphoneos*] = iPhone Developer

Video format or MIME type is not supported

In my case, this error:

Video format or MIME type is not supported.

Was due to the CSP in my .htaccess that did not allow the content to be loaded. You can check this by opening the browser's console and refreshing the page.

Once I added the domain that was hosting the video in the media-src part of that CSP, the console was clean and the video was loaded properly. Example:

Content-Security-Policy: default-src 'none'; media-src https://myvideohost.domain; script-src 'self'; style-src 'unsafe-inline' 'self'

Where to place JavaScript in an HTML file?

I would say that it depends of fact what do you planed to achieve with Javascript code:

  • if you planned to insert external your JS script(s), then the best place is in head of the page
  • if you planed to use pages on smartphones, then bottom of page, just before tag.
  • but, if you planned to make combination HTML and JS (dynamically created and populated HTML table, for example) then you must put it where you need it there.

C# removing items from listbox

protected void lbAddtoDestination_Click(object sender, EventArgs e)
        {
            AddRemoveItemsListBox(lstSourceSkills, lstDestinationSkills);
        }
        protected void lbRemovefromDestination_Click(object sender, EventArgs e)
        {
            AddRemoveItemsListBox(lstDestinationSkills, lstSourceSkills);
        }
        private void AddRemoveItemsListBox(ListBox source, ListBox destination)
        {
            List<ListItem> toBeRemoved = new List<ListItem>();
            foreach (ListItem item in source.Items)
            {
                if (item.Selected)
                {
                    toBeRemoved.Add(item);
                    destination.Items.Add(item);
                }
            }
            foreach (ListItem item in toBeRemoved) source.Items.Remove(item);
        }

Subtract a value from every number in a list in Python?

You can use map() function:

a = list(map(lambda x: x - 13, a))

Wi-Fi Direct and iOS Support

It took me a while to find out what is going on, but here is the summary. I hope this save people a lot of time.

Apple are not playing nice with Wi-Fi Direct, not in the same way that Android is. The Multipeer Connectivity Framework that Apple provides combines both BLE and WiFi Direct together and will only work with Apple devices and not any device that is using Wi-Fi Direct.

https://developer.apple.com/library/ios/documentation/MultipeerConnectivity/Reference/MultipeerConnectivityFramework/index.html

It states the following in this documentation - "The Multipeer Connectivity framework provides support for discovering services provided by nearby iOS devices using infrastructure Wi-Fi networks, peer-to-peer Wi-Fi, and Bluetooth personal area networks and subsequently communicating with those services by sending message-based data, streaming data, and resources (such as files)."

Additionally, Wi-Fi direct in this mode between i-Devices will need iPhone 5 and above.

There are apps that use a form of Wi-Fi Direct on the App Store, but these are using their own libraries.

node.js shell command execution

I had a similar problem and I ended up writing a node extension for this. You can check out the git repository. It's open source and free and all that good stuff !

https://github.com/aponxi/npm-execxi

ExecXI is a node extension written in C++ to execute shell commands one by one, outputting the command's output to the console in real-time. Optional chained, and unchained ways are present; meaning that you can choose to stop the script after a command fails (chained), or you can continue as if nothing has happened !

Usage instructions are in the ReadMe file. Feel free to make pull requests or submit issues!

I thought it was worth to mention it.

Converting an array to a function arguments list

A very readable example from another post on similar topic:

var args = [ 'p0', 'p1', 'p2' ];

function call_me (param0, param1, param2 ) {
    // ...
}

// Calling the function using the array with apply()
call_me.apply(this, args);

And here a link to the original post that I personally liked for its readability

"Keep Me Logged In" - the best approach

Implementing a "Keep Me Logged In" feature means you need to define exactly what that will mean to the user. In the simplest case, I would use that to mean the session has a much longer timeout: 2 days (say) instead of 2 hours. To do that, you will need your own session storage, probably in a database, so you can set custom expiry times for the session data. Then you need to make sure you set a cookie that will stick around for a few days (or longer), rather than expire when they close the browser.

I can hear you asking "why 2 days? why not 2 weeks?". This is because using a session in PHP will automatically push the expiry back. This is because a session's expiry in PHP is actually an idle timeout.

Now, having said that, I'd probably implement a harder timeout value that I store in the session itself, and out at 2 weeks or so, and add code to see that and to forcibly invalidate the session. Or at least to log them out. This will mean that the user will be asked to login periodically. Yahoo! does this.

Can anyone explain IEnumerable and IEnumerator to me?

  • An object implementing IEnumerable allows others to visit each of its items (by an enumerator).
  • An object implementing IEnumerator is the doing the iteration. It's looping over an enumerable object.

Think of enumerable objects as of lists, stacks, trees.

How to change the author and committer name and e-mail of multiple commits in Git?

You can also do:

git filter-branch --commit-filter '
        if [ "$GIT_COMMITTER_NAME" = "<Old Name>" ];
        then
                GIT_COMMITTER_NAME="<New Name>";
                GIT_AUTHOR_NAME="<New Name>";
                GIT_COMMITTER_EMAIL="<New Email>";
                GIT_AUTHOR_EMAIL="<New Email>";
                git commit-tree "$@";
        else
                git commit-tree "$@";
        fi' HEAD

Note, if you are using this command in the Windows command prompt, then you need to use " instead of ':

git filter-branch --commit-filter "
        if [ "$GIT_COMMITTER_NAME" = "<Old Name>" ];
        then
                GIT_COMMITTER_NAME="<New Name>";
                GIT_AUTHOR_NAME="<New Name>";
                GIT_COMMITTER_EMAIL="<New Email>";
                GIT_AUTHOR_EMAIL="<New Email>";
                git commit-tree "$@";
        else
                git commit-tree "$@";
        fi" HEAD

Programmatically Hide/Show Android Soft Keyboard

Did you try InputMethodManager.SHOW_IMPLICIT in first window.

and for hiding in second window use InputMethodManager.HIDE_IMPLICIT_ONLY

EDIT :

If its still not working then probably you are putting it at the wrong place. Override onFinishInflate() and show/hide there.

@override
public void onFinishInflate() {
     /* code to show keyboard on startup */
    InputMethodManager imm = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
    imm.showSoftInput(mUserNameEdit, InputMethodManager.SHOW_IMPLICIT);
}

Getting user input

In python 3.x, use input() instead of raw_input()

kill -3 to get java thread dump

In the same location where the JVM's stdout is placed. If you have a Tomcat server, this will be the catalina_(date).out file.

Python map object is not subscriptable

In Python 3, map returns an iterable object of type map, and not a subscriptible list, which would allow you to write map[i]. To force a list result, write

payIntList = list(map(int,payList))

However, in many cases, you can write out your code way nicer by not using indices. For example, with list comprehensions:

payIntList = [pi + 1000 for pi in payList]
for pi in payIntList:
    print(pi)

Is it possible to create a File object from InputStream

If you are using Java version 7 or higher, you can use try-with-resources to properly close the FileOutputStream. The following code use IOUtils.copy() from commons-io.

public void copyToFile(InputStream inputStream, File file) throws IOException {
    try(OutputStream outputStream = new FileOutputStream(file)) {
        IOUtils.copy(inputStream, outputStream);
    }
}  

Counting how many times a certain char appears in a string before any other char appears

One approach you could take is the following method:

// Counts how many of a certain character occurs in the given string
public static int CharCountInString(char chr, string str)
{
    return str.Split(chr).Length-1;
}

As per the parameters this method returns the count of a specific character within a specific string.

This method works by splitting the string into an array by the specified character and then returning the length of that array -1.

Python subprocess.Popen "OSError: [Errno 12] Cannot allocate memory"

Have you tried using:

(status,output) = commands.getstatusoutput("ps aux")

I thought this had fixed the exact same problem for me. But then my process ended up getting killed instead of failing to spawn, which is even worse..

After some testing I found that this only occurred on older versions of python: it happens with 2.6.5 but not with 2.7.2

My search had led me here python-close_fds-issue, but unsetting closed_fds had not solved the issue. It is still well worth a read.

I found that python was leaking file descriptors by just keeping an eye on it:

watch "ls /proc/$PYTHONPID/fd | wc -l"

Like you, I do want to capture the command's output, and I do want to avoid OOM errors... but it looks like the only way is for people to use a less buggy version of Python. Not ideal...

Why does this code using random strings print "hello world"?

The principal is the Random Class constructed with the same seed will generate the same pattern of numbers every time.

Getting an attribute value in xml element

Below is the code to do it in vtd-xml. It basically queries the XML with the XPath of "/xml/item/@name."

import com.ximpleware.*;

public class getAttrs{

   public static void main(String[] s) throws VTDException{
         VTDGen vg = new VTDGen();
         if (!vg.parseFile("input.xml",false)) // turn off namespace
              return;
         VTDNav vn = vg.getNav();
         AutoPilot ap =  new AutoPilot(vn);
         ap.selectXPath("/xml/item/@name");
         int i=0;
         while( (i=ap.evalXPath())!=-1){
              System.out.println(" item name is ===>"+vn.toString(i+1)); 
         }
   }
}

How to repair a serialized string which has been corrupted by an incorrect byte count length?

public function unserializeKeySkills($string) {
    $output = array();
    $string = trim(preg_replace('/\s\s+/', ' ',$string));
    $string = preg_replace_callback('!s:(\d+):"(.*?)";!', function($m) { return 's:'.strlen($m[2]).':"'.$m[2].'";'; }, utf8_encode( trim(preg_replace('/\s\s+/', ' ',$string)) ));
    try {
        $output =  unserialize($string);
    } catch (\Exception $e) {
        \Log::error("unserialize Data : " .print_r($string,true));
    }
    return $output;
}

Change mysql user password using command line

In windows 10, just exit out of current login and run this on command line

--> mysqladmin -u root password “newpassword”

where instead of root could be any user.

Submitting a multidimensional array via POST with php

you could submit all parameters with such naming:

params[0][topdiameter]
params[0][bottomdiameter]
params[1][topdiameter]
params[1][bottomdiameter]

then later you do something like this:

foreach ($_REQUEST['params'] as $item) {
    echo $item['topdiameter'];
    echo $item['bottomdiameter'];
}

Batch Files - Error Handling

Its extremely easy! Create a file that contains:

call <filename>  // the file you made
cls
echo An error occured!
<Your commands>
pause

So now when you start it, it will launch your program as normal. But when anything goes wrong it exits and continues the script inside the first file. Now there you can put your own commands in.

Uncaught Typeerror: cannot read property 'innerHTML' of null

run the code after your html structure in the body statement

    <html>
    <body>
    <p>asdasd</p>
    <p>asdasd</p>
    <p>asdasd</p>
    <script src="myfile.js"></script>
    </body>
    </html>

ASP.NET Setting width of DataBound column in GridView

hey recently i figured it out how to set width if your gridview databound with sql dataset.first set these control RowStyle-Wrap="false" HeaderStyle-Wrap="false" and then you can set the column width as much as you like. ex : ItemStyle-Width="150px" HeaderStyle-Width="150px"

How to remove extension from string (only real extension!)

From the manual, pathinfo:

<?php
    $path_parts = pathinfo('/www/htdocs/index.html');

    echo $path_parts['dirname'], "\n";
    echo $path_parts['basename'], "\n";
    echo $path_parts['extension'], "\n";
    echo $path_parts['filename'], "\n"; // Since PHP 5.2.0
?>

It doesn't have to be a complete path to operate properly. It will just as happily parse file.jpg as /path/to/my/file.jpg.

ASP.NET Identity DbContext confusion

This is a late entry for folks, but below is my implementation. You will also notice I stubbed-out the ability to change the the KEYs default type: the details about which can be found in the following articles:

NOTES:
It should be noted that you cannot use Guid's for your keys. This is because under the hood they are a Struct, and as such, have no unboxing which would allow their conversion from a generic <TKey> parameter.

THE CLASSES LOOK LIKE:

public class ApplicationDbContext : IdentityDbContext<ApplicationUser, CustomRole, string, CustomUserLogin, CustomUserRole, CustomUserClaim>
{
    #region <Constructors>

    public ApplicationDbContext() : base(Settings.ConnectionString.Database.AdministrativeAccess)
    {
    }

    #endregion

    #region <Properties>

    //public DbSet<Case> Case { get; set; }

    #endregion

    #region <Methods>

    #region

    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        base.OnModelCreating(modelBuilder);

        //modelBuilder.Configurations.Add(new ResourceConfiguration());
        //modelBuilder.Configurations.Add(new OperationsToRolesConfiguration());
    }

    #endregion

    #region

    public static ApplicationDbContext Create()
    {
        return new ApplicationDbContext();
    }

    #endregion

    #endregion
}

    public class ApplicationUser : IdentityUser<string, CustomUserLogin, CustomUserRole, CustomUserClaim>
    {
        #region <Constructors>

        public ApplicationUser()
        {
            Init();
        }

        #endregion

        #region <Properties>

        [Required]
        [StringLength(250)]
        public string FirstName { get; set; }

        [Required]
        [StringLength(250)]
        public string LastName { get; set; }

        #endregion

        #region <Methods>

        #region private

        private void Init()
        {
            Id = Guid.Empty.ToString();
        }

        #endregion

        #region public

        public async Task<ClaimsIdentity> GenerateUserIdentityAsync(UserManager<ApplicationUser, string> manager)
        {
            // Note the authenticationType must match the one defined in CookieAuthenticationOptions.AuthenticationType
            var userIdentity = await manager.CreateIdentityAsync(this, DefaultAuthenticationTypes.ApplicationCookie);

            // Add custom user claims here

            return userIdentity;
        }

        #endregion

        #endregion
    }

    public class CustomUserStore : UserStore<ApplicationUser, CustomRole, string, CustomUserLogin, CustomUserRole, CustomUserClaim>
    {
        #region <Constructors>

        public CustomUserStore(ApplicationDbContext context) : base(context)
        {
        }

        #endregion
    }

    public class CustomUserRole : IdentityUserRole<string>
    {
    }

    public class CustomUserLogin : IdentityUserLogin<string>
    {
    }

    public class CustomUserClaim : IdentityUserClaim<string> 
    { 
    }

    public class CustomRoleStore : RoleStore<CustomRole, string, CustomUserRole>
    {
        #region <Constructors>

        public CustomRoleStore(ApplicationDbContext context) : base(context)
        {
        } 

        #endregion
    }

    public class CustomRole : IdentityRole<string, CustomUserRole>
    {
        #region <Constructors>

        public CustomRole() { }
        public CustomRole(string name) 
        { 
            Name = name; 
        }

        #endregion
    }

How to set only time part of a DateTime variable in C#

I'm not sure exactly what you're trying to do but you can set the date/time to exactly what you want in a number of ways...

You can specify 12/25/2010 4:58 PM by using

DateTime myDate = Convert.ToDateTime("2010-12-25 16:58:00");

OR if you have an existing datetime construct , say 12/25/2010 (and any random time) and you want to set it to 12/25/2010 4:58 PM, you could do so like this:

DateTime myDate = ExistingTime.Date.AddHours(16).AddMinutes(58);

The ExistingTime.Date will be 12/25 at midnight, and you just add hours and minutes to get it to the time you want.

How to solve npm error "npm ERR! code ELIFECYCLE"

React Application: For me the issue was that after running npm install had some errors.

I've went with the recommendation npm audit fix. This operation broke my package.json and package-lock.json (changed version of packages and and structure of .json).

THE FIX WAS:

  • Delete node_modules
  • Run npm install
  • npm start

Hope this will be helpfull for someone.

Google MAP API v3: Center & Zoom on displayed markers

I've also find this fix that zooms to fit all markers

LatLngList: an array of instances of latLng, for example:

// "map" is an instance of GMap3

var LatLngList = [
                     new google.maps.LatLng (52.537,-2.061), 
                     new google.maps.LatLng (52.564,-2.017)
                 ],
    latlngbounds = new google.maps.LatLngBounds();

LatLngList.forEach(function(latLng){
   latlngbounds.extend(latLng);
});

// or with ES6:
// for( var latLng of LatLngList)
//    latlngbounds.extend(latLng);

map.setCenter(latlngbounds.getCenter());
map.fitBounds(latlngbounds); 

Finding the number of days between two dates

I read all previous solutions, none of them use PHP 5.3 tools: DateTime::Diff and DateInterval::Days

DateInterval::Days contains exactly the right numbers of days between to date. It is not necessary to create something special and bizarre.

/**
 * We suppose that PHP is configured in UTC
 * php.ini configuration:
 * [Date]
 * ; Defines the default timezone used by the date functions
 * ; http://php.net/date.timezone
 * date.timezone = UTC
 * @link http://php.net/date.timezone
 */

/**
 * getDaysBetween2Dates
 *
 * Return the difference of days between $date1 and $date2 ($date1 - $date2)
 * if $absolute parameter is false, the return value is negative if $date2 is after than $date1
 *
 * @param DateTime $date1
 * @param DateTime $date2
 * @param Boolean $absolute
 *            = true
 * @return integer
 */
function getDaysBetween2Dates(DateTime $date1, DateTime $date2, $absolute = true)
{
    $interval = $date2->diff($date1);
    // if we have to take in account the relative position (!$absolute) and the relative position is negative,
    // we return negatif value otherwise, we return the absolute value
    return (!$absolute and $interval->invert) ? - $interval->days : $interval->days;
}

echo '<h3>2020-03-01 - 2020-02-01: 29 days as it\'s a standard leap year</h3>';
echo getDaysBetween2Dates(new DateTime("2020-03-01"), new DateTime("2020-02-01"), false);

echo '<h3>1900-03-01 - 1900-02-01: 28 days as it\'s a "standard" century</h3>';
echo getDaysBetween2Dates(new DateTime("1900-03-01"), new DateTime("1900-02-01"), false);

echo '<h3>2000-03-01 - 2000-02-01: 29 days as it\'s a century multiple of 400: 2000=400x5</h3>';
echo getDaysBetween2Dates(new DateTime("2000-03-01"), new DateTime("2000-02-01"), false);

echo '<h3>2020-03-01 - 2020-04-01: -28 days as 2020-03-01 is before 2020-04-01</h3>';
echo getDaysBetween2Dates(new DateTime("2020-02-01"), new DateTime("2020-03-01"), false);

What is the OR operator in an IF statement

The OR operator is a double pipe:

||

So it looks like:

if (this || that) 
{
  //do the other thing
}

EDIT: The reason that your updated attempt isn't working is because the logical operators must separate valid C# expressions. Expressions have operands and operators and operators have an order of precedence.

In your case, the == operator is evaluated first. This means your expression is being evaluated as (title == "User greeting") || "User name". The || gets evaluated next. Since || requires each operand to be a boolean expression, it fails, because your operands are strings.

Using two separate boolean expressions will ensure that your || operator will work properly.

title == "User greeting" || title == "User name"

Calling a function from a string in C#

Yes. You can use reflection. Something like this:

Type thisType = this.GetType();
MethodInfo theMethod = thisType.GetMethod(TheCommandString);
theMethod.Invoke(this, userParameters);

Understanding Linux /proc/id/maps

memory mapping is not only used to map files into memory but is also a tool to request RAM from kernel. These are those inode 0 entries - your stack, heap, bss segments and more

Iterating over and deleting from Hashtable in Java

You need to use an explicit java.util.Iterator to iterate over the Map's entry set rather than being able to use the enhanced For-loop syntax available in Java 6. The following example iterates over a Map of Integer, String pairs, removing any entry whose Integer key is null or equals 0.

Map<Integer, String> map = ...

Iterator<Map.Entry<Integer, String>> it = map.entrySet().iterator();

while (it.hasNext()) {
  Map.Entry<Integer, String> entry = it.next();

  // Remove entry if key is null or equals 0.
  if (entry.getKey() == null || entry.getKey() == 0) {
    it.remove();
  }
}

Can multiple different HTML elements have the same ID if they're different elements?

It's possible to have duplicate ids. I have tried adding the todoitem from javascript and it added to the dom successfully. This is the html code and javscript code. I have tried adding the todoitem from javascript and it added to the dom successfully. This is the html code.

This is the javascript code.

How do you auto format code in Visual Studio?

In VS 2017 and 2019

Format Document is CTRL E + D.

But...if you want to add the Format Document button to a tool bar do this.
Right click on tool bar.
Select "Customize.."
Select the "Commands" Tab.
Select the "Toolbar" radio button.
Select "Text Editor" from the pull down next to the radio button (or what ever tool bar you want the botton on)

Now...

Click the Add Command button.
Categories: Edit
Commands: Document Format
Click OK

IntelliJ: Working on multiple projects

For who uses Gradle can also avail the same:

enter image description here

enter image description here

Go to: 1. View --> Tool Windows --> Gradle 2. Click on the + button and add your build.gradle file

How to get the unique ID of an object which overrides hashCode()?

Maybe this quick, dirty solution will work?

public class A {
    static int UNIQUE_ID = 0;
    int uid = ++UNIQUE_ID;

    public int hashCode() {
        return uid;
    }
}

This also gives the number of instance of a class being initialized.

Add vertical whitespace using Twitter Bootstrap?

Just use <br/>. I found myself here looking for the answer to this question and then felt sort of silly for not thinking about using a simple line break as suggested by user JayKilleen in a comment.

base 64 encode and decode a string in angular (2+)

Use btoa() for encode and atob() for decode

text_val:any="your encoding text";

Encoded Text: console.log(btoa(this.text_val)); //eW91ciBlbmNvZGluZyB0ZXh0

Decoded Text: console.log(atob("eW91ciBlbmNvZGluZyB0ZXh0")); //your encoding text

Check if a input box is empty

The above answer didn't work with Angular 6. So following is how I resolved it. Lets say this is how I defined my input box -

_x000D_
_x000D_
<input type="number" id="myTextBox" name="myTextBox"_x000D_
 [(ngModel)]="response.myTextBox"_x000D_
            #myTextBox="ngModel">
_x000D_
_x000D_
_x000D_

To check if the field is empty or not this should be the script.

_x000D_
_x000D_
<div *ngIf="!myTextBox.value" style="color:red;">_x000D_
 Your field is empty_x000D_
</div>
_x000D_
_x000D_
_x000D_

Do note the subtle difference between the above answer and this answer. I have added an additional attribute .value after my input name myTextBox. I don't know if the above answer worked for above version of Angular, but for Angular 6 this is how it should be done.

Some more explanation on why this check works; when there is no value present in the input box the default value of myTextBox.value will be undefined. As soon as you enter some text, your text becomes the new value of myTextBox.value.

When your check is !myTextBox.value it is checking that the value is undefined or not, it is equivalent to myTextBox.value == undefined.

How can I set multiple CSS styles in JavaScript?

You can have individual classes in your css files and then assign the classname to your element

or you can loop through properties of styles as -

var css = { "font-size": "12px", "left": "200px", "top": "100px" };

for(var prop in css) {
  document.getElementById("myId").style[prop] = css[prop];
}

How to see the changes in a Git commit?

First get the commit ID using,

git log #to list all

Or

git log -p -1 #last one commit id

Copy commit id.

Now we use two methods to list changes from a specific commit,

Method 1:

git diff commit_id^! #commit id something like this 1c6a6000asad012

Method 2:

git show commit_id
For example: git show 1c6a600a

List of lists into numpy array

It's as simple as:

>>> lists = [[1, 2], [3, 4]]
>>> np.array(lists)
array([[1, 2],
       [3, 4]])

How to temporarily disable a click handler in jQuery?

$("#button_id").click(function() {
  if($(this).data('dont')==1) return;
  $(this).data('dont',1);
  //do something
  $(this).data('dont',0);
}

Remeber that $.data() would work only for items with ID.

Ruby max integer

Reading the friendly manual? Who'd want to do that?

start = Time.now
largest_known_fixnum = 1
smallest_known_bignum = nil

until smallest_known_bignum == largest_known_fixnum + 1
  if smallest_known_bignum.nil?
    next_number_to_try = largest_known_fixnum * 1000
  else
    next_number_to_try = (smallest_known_bignum + largest_known_fixnum) / 2 # Geometric mean would be more efficient, but more risky
  end

  if next_number_to_try <= largest_known_fixnum ||
       smallest_known_bignum && next_number_to_try >= smallest_known_bignum
    raise "Can't happen case" 
  end

  case next_number_to_try
    when Bignum then smallest_known_bignum = next_number_to_try
    when Fixnum then largest_known_fixnum = next_number_to_try
    else raise "Can't happen case"
  end
end

finish = Time.now
puts "The largest fixnum is #{largest_known_fixnum}"
puts "The smallest bignum is #{smallest_known_bignum}"
puts "Calculation took #{finish - start} seconds"

Select records from today, this week, this month php mysql

A better solution for "today" is:

SELECT * FROM jokes WHERE DATE(date) = DATE(NOW())

How to use ConcurrentLinkedQueue?

This is largely a duplicate of another question.

Here's the section of that answer that is relevant to this question:

Do I need to do my own synchronization if I use java.util.ConcurrentLinkedQueue?

Atomic operations on the concurrent collections are synchronized for you. In other words, each individual call to the queue is guaranteed thread-safe without any action on your part. What is not guaranteed thread-safe are any operations you perform on the collection that are non-atomic.

For example, this is threadsafe without any action on your part:

queue.add(obj);

or

queue.poll(obj);

However; non-atomic calls to the queue are not automatically thread-safe. For example, the following operations are not automatically threadsafe:

if(!queue.isEmpty()) {
   queue.poll(obj);
}

That last one is not threadsafe, as it is very possible that between the time isEmpty is called and the time poll is called, other threads will have added or removed items from the queue. The threadsafe way to perform this is like this:

synchronized(queue) {
    if(!queue.isEmpty()) {
       queue.poll(obj);
    }
}

Again...atomic calls to the queue are automatically thread-safe. Non-atomic calls are not.

Make Bootstrap's Carousel both center AND responsive?

None of the above solutions worked for me. It's possible that there were some other styles conflicting.

For myself, the following worked, hopefully it may help someone else. I'm using bootstrap 4.

.carousel-inner img {       
   display:block;
   height: auto; 
   max-width: 100%;
}

How to use the gecko executable with Selenium

The solutions above work fine for local testing and firing up browsers from the java code.If you fancy firing up your selenium grid later then this parameter is a must have in order to tell the remote node where to find the geckodriver:

-Dwebdriver.gecko.driver="C:\geckodriver\geckodriver.exe"

The node cannot find the gecko driver when specified in the Automation Java code.

So the complete command for the node whould be (assuming node and hub for test purposes live on same machine) :

java -Dwebdriver.gecko.driver="C:\geckodriver\geckodriver.exe" -jar selenium-server-standalone-2.53.0.jar -role node -hub http://localhost:4444/grid/register

And you should expect to see in the node log :

00:35:44.383 INFO - Launching a Selenium Grid node
Setting system property webdriver.gecko.driver to C:\geckodriver\geckodriver.exe

How to set the image from drawable dynamically in android?

imageview= (ImageView)findViewById(R.id.imageView);
imageview.setImageResource(R.drawable.mydrawable);

C - determine if a number is prime

After reading this question, I was intrigued by the fact that some answers offered optimization by running a loop with multiples of 2*3=6.

So I create a new function with the same idea, but with multiples of 2*3*5=30.

int check235(unsigned long n)
{
    unsigned long sq, i;

    if(n<=3||n==5)
        return n>1;

    if(n%2==0 || n%3==0 || n%5==0)
        return 0;

    if(n<=30)
        return checkprime(n); /* use another simplified function */

    sq=ceil(sqrt(n));
    for(i=7; i<=sq; i+=30)
        if (n%i==0 || n%(i+4)==0 || n%(i+6)==0 || n%(i+10)==0 || n%(i+12)==0 
           || n%(i+16)==0 || n%(i+22)==0 || n%(i+24)==0)
            return 0;

        return 1;
}

By running both functions and checking times I could state that this function is really faster. Lets see 2 tests with 2 different primes:

$ time ./testprimebool.x 18446744069414584321 0
f(2,3)
Yes, its prime.    
real    0m14.090s
user    0m14.096s
sys     0m0.000s

$ time ./testprimebool.x 18446744069414584321 1
f(2,3,5)
Yes, its prime.    
real    0m9.961s
user    0m9.964s
sys     0m0.000s

$ time ./testprimebool.x 18446744065119617029 0
f(2,3)
Yes, its prime.    
real    0m13.990s
user    0m13.996s
sys     0m0.004s

$ time ./testprimebool.x 18446744065119617029 1
f(2,3,5)
Yes, its prime.    
real    0m10.077s
user    0m10.068s
sys     0m0.004s

So I thought, would someone gain too much if generalized? I came up with a function that will do a siege first to clean a given list of primordial primes, and then use this list to calculate the bigger one.

int checkn(unsigned long n, unsigned long *p, unsigned long t)
{
    unsigned long sq, i, j, qt=1, rt=0;
    unsigned long *q, *r;

    if(n<2)
        return 0;

    for(i=0; i<t; i++)
    {
        if(n%p[i]==0)
            return 0;
        qt*=p[i];
    }
    qt--;

    if(n<=qt)
        return checkprime(n); /* use another simplified function */

    if((q=calloc(qt, sizeof(unsigned long)))==NULL)
    {
        perror("q=calloc()");
        exit(1);
    }
    for(i=0; i<t; i++)
        for(j=p[i]-2; j<qt; j+=p[i])
            q[j]=1;

    for(j=0; j<qt; j++)
        if(q[j])
            rt++;

    rt=qt-rt;
    if((r=malloc(sizeof(unsigned long)*rt))==NULL)
    {
        perror("r=malloc()");
        exit(1);
    }
    i=0;
    for(j=0; j<qt; j++)
        if(!q[j])
            r[i++]=j+1;

    free(q);

    sq=ceil(sqrt(n));
    for(i=1; i<=sq; i+=qt+1)
    {
        if(i!=1 && n%i==0)
            return 0;
        for(j=0; j<rt; j++)
            if(n%(i+r[j])==0)
                return 0;
    }
    return 1;
}

I assume I did not optimize the code, but it's fair. Now, the tests. Because so many dynamic memory, I expected the list 2 3 5 to be a little slower than the 2 3 5 hard-coded. But it was ok as you can see bellow. After that, time got smaller and smaller, culminating the best list to be:

2 3 5 7 11 13 17 19

With 8.6 seconds. So if someone would create a hardcoded program that makes use of such technique I would suggest use the list 2 3 and 5, because the gain is not that big. But also, if willing to code, this list is ok. Problem is you cannot state all cases without a loop, or your code would be very big (There would be 1658879 ORs, that is || in the respective internal if). The next list:

2 3 5 7 11 13 17 19 23

time started to get bigger, with 13 seconds. Here the whole test:

$ time ./testprimebool.x 18446744065119617029 2 3 5
f(2,3,5)
Yes, its prime.
real    0m12.668s
user    0m12.680s
sys     0m0.000s

$ time ./testprimebool.x 18446744065119617029 2 3 5 7
f(2,3,5,7)
Yes, its prime.
real    0m10.889s
user    0m10.900s
sys     0m0.000s

$ time ./testprimebool.x 18446744065119617029 2 3 5 7 11
f(2,3,5,7,11)
Yes, its prime.
real    0m10.021s
user    0m10.028s
sys     0m0.000s

$ time ./testprimebool.x 18446744065119617029 2 3 5 7 11 13
f(2,3,5,7,11,13)
Yes, its prime.
real    0m9.351s
user    0m9.356s
sys     0m0.004s

$ time ./testprimebool.x 18446744065119617029 2 3 5 7 11 13 17
f(2,3,5,7,11,13,17)
Yes, its prime.
real    0m8.802s
user    0m8.800s
sys     0m0.008s

$ time ./testprimebool.x 18446744065119617029 2 3 5 7 11 13 17 19
f(2,3,5,7,11,13,17,19)
Yes, its prime.
real    0m8.614s
user    0m8.564s
sys     0m0.052s

$ time ./testprimebool.x 18446744065119617029 2 3 5 7 11 13 17 19 23
f(2,3,5,7,11,13,17,19,23)
Yes, its prime.
real    0m13.013s
user    0m12.520s
sys     0m0.504s

$ time ./testprimebool.x 18446744065119617029 2 3 5 7 11 13 17 19 23 29
f(2,3,5,7,11,13,17,19,23,29)                                                                                                                         
q=calloc(): Cannot allocate memory

PS. I did not free(r) intentionally, giving this task to the OS, as the memory would be freed as soon as the program exited, to gain some time. But it would be wise to free it if you intend to keep running your code after the calculation.


BONUS

int check2357(unsigned long n)
{
    unsigned long sq, i;

    if(n<=3||n==5||n==7)
        return n>1;

    if(n%2==0 || n%3==0 || n%5==0 || n%7==0)
        return 0;

    if(n<=210)
        return checkprime(n); /* use another simplified function */

    sq=ceil(sqrt(n));
    for(i=11; i<=sq; i+=210)
    {    
        if(n%i==0 || n%(i+2)==0 || n%(i+6)==0 || n%(i+8)==0 || n%(i+12)==0 || 
   n%(i+18)==0 || n%(i+20)==0 || n%(i+26)==0 || n%(i+30)==0 || n%(i+32)==0 || 
   n%(i+36)==0 || n%(i+42)==0 || n%(i+48)==0 || n%(i+50)==0 || n%(i+56)==0 || 
   n%(i+60)==0 || n%(i+62)==0 || n%(i+68)==0 || n%(i+72)==0 || n%(i+78)==0 || 
   n%(i+86)==0 || n%(i+90)==0 || n%(i+92)==0 || n%(i+96)==0 || n%(i+98)==0 || 
   n%(i+102)==0 || n%(i+110)==0 || n%(i+116)==0 || n%(i+120)==0 || n%(i+126)==0 || 
   n%(i+128)==0 || n%(i+132)==0 || n%(i+138)==0 || n%(i+140)==0 || n%(i+146)==0 || 
   n%(i+152)==0 || n%(i+156)==0 || n%(i+158)==0 || n%(i+162)==0 || n%(i+168)==0 || 
   n%(i+170)==0 || n%(i+176)==0 || n%(i+180)==0 || n%(i+182)==0 || n%(i+186)==0 || 
   n%(i+188)==0 || n%(i+198)==0)
            return 0;
    }
    return 1;
}

Time:

$ time ./testprimebool.x 18446744065119617029 7
h(2,3,5,7)
Yes, its prime.
real    0m9.123s
user    0m9.132s
sys     0m0.000s

Replace only some groups with Regex

Here is a version similar to Daniel's but replacing multiple matches:

public static string ReplaceGroup(string input, string pattern, RegexOptions options, string groupName, string replacement)
{
    Match match;
    while ((match = Regex.Match(input, pattern, options)).Success)
    {
        var group = match.Groups[groupName];

        var sb = new StringBuilder();

        // Anything before the match
        if (match.Index > 0)
            sb.Append(input.Substring(0, match.Index));

        // The match itself
        var startIndex = group.Index - match.Index;
        var length = group.Length;
        var original = match.Value;
        var prior = original.Substring(0, startIndex);
        var trailing = original.Substring(startIndex + length);
        sb.Append(prior);
        sb.Append(replacement);
        sb.Append(trailing);

        // Anything after the match
        if (match.Index + match.Length < input.Length)
            sb.Append(input.Substring(match.Index + match.Length));

        input = sb.ToString();
    }

    return input;

Sort objects in ArrayList by date?

You can make your object comparable:

public static class MyObject implements Comparable<MyObject> {

  private Date dateTime;

  public Date getDateTime() {
    return dateTime;
  }

  public void setDateTime(Date datetime) {
    this.dateTime = datetime;
  }

  @Override
  public int compareTo(MyObject o) {
    return getDateTime().compareTo(o.getDateTime());
  }
}

And then you sort it by calling:

Collections.sort(myList);

However sometimes you don't want to change your model, like when you want to sort on several different properties. In that case, you can create comparator on the fly:

Collections.sort(myList, new Comparator<MyObject>() {
  public int compare(MyObject o1, MyObject o2) {
      return o1.getDateTime().compareTo(o2.getDateTime());
  }
});

However, the above works only if you're certain that dateTime is not null at the time of comparison. It's wise to handle null as well to avoid NullPointerExceptions:

public static class MyObject implements Comparable<MyObject> {

  private Date dateTime;

  public Date getDateTime() {
    return dateTime;
  }

  public void setDateTime(Date datetime) {
    this.dateTime = datetime;
  }

  @Override
  public int compareTo(MyObject o) {
    if (getDateTime() == null || o.getDateTime() == null)
      return 0;
    return getDateTime().compareTo(o.getDateTime());
  }
}

Or in the second example:

Collections.sort(myList, new Comparator<MyObject>() {
  public int compare(MyObject o1, MyObject o2) {
      if (o1.getDateTime() == null || o2.getDateTime() == null)
        return 0;
      return o1.getDateTime().compareTo(o2.getDateTime());
  }
});

java.lang.VerifyError: Expecting a stackmap frame at branch target JDK 1.7

Sorry for digging, but I met the same problem and found the simplier solution.

In Java compiler options you need to uncheck "Preserve unused (never read) local variables" so there is no need to change back target JVM version.

It seems to be a bug in an older Eclipe versions.

Finding the max/min value in an array of primitives using Java

import java.util.Random;

public class Main {

public static void main(String[] args) {
   int a[] = new int [100];
   Random rnd = new Random ();

    for (int i = 0; i< a.length; i++) {
        a[i] = rnd.nextInt(99-0)+0;
        System.out.println(a[i]);
    }

    int max = 0;          

    for (int i = 0; i < a.length; i++) {
        a[i] = max;


        for (int j = i+1; j<a.length; j++) {
            if (a[j] > max) {
               max = a[j];
            }

        }
    }

    System.out.println("Max element: " + max);
}
}

.setAttribute("disabled", false); changes editable attribute to false

A disabled element is, (self-explaining) disabled and thereby logically not editable, so:

set the disabled attribute [...] changes the editable attribute too

Is an intended and well-defined behaviour.

The real problem here seems to be you're trying to set disabled to false via setAttribute() which doesn't do what you're expecting. an element is disabled if the disabled-attribute is set, independent of it's value (so, disabled="true", disabled="disabled" and disabled="false" all do the same: the element gets disabled). you should instead remove the complete attribute:

element.removeAttribute("disabled");

or set that property directly:

element.disabled = false;

Find a line in a file and remove it

This solution may not be optimal or pretty, but it works. It reads in an input file line by line, writing each line out to a temporary output file. Whenever it encounters a line that matches what you are looking for, it skips writing that one out. It then renames the output file. I have omitted error handling, closing of readers/writers, etc. from the example. I also assume there is no leading or trailing whitespace in the line you are looking for. Change the code around trim() as needed so you can find a match.

File inputFile = new File("myFile.txt");
File tempFile = new File("myTempFile.txt");

BufferedReader reader = new BufferedReader(new FileReader(inputFile));
BufferedWriter writer = new BufferedWriter(new FileWriter(tempFile));

String lineToRemove = "bbb";
String currentLine;

while((currentLine = reader.readLine()) != null) {
    // trim newline when comparing with lineToRemove
    String trimmedLine = currentLine.trim();
    if(trimmedLine.equals(lineToRemove)) continue;
    writer.write(currentLine + System.getProperty("line.separator"));
}
writer.close(); 
reader.close(); 
boolean successful = tempFile.renameTo(inputFile);

How to Animate Addition or Removal of Android ListView Rows

call listView.scheduleLayoutAnimation(); before changing the list

jQuery getTime function

Yes, it is possible:

jQuery.now()

or simply

$.now()

see jQuery Documentation for jQuery.now()

Comparing two .jar files

How to install libusb in Ubuntu

First,

sudo apt-get install libusb-1.0-0-dev

updatedb && locate libusb.h.

Second, replace <libusb.h> with <libusb-1.0/libusb.h>.

update:

don't need to change any file.just add this to your Makefile.

`pkg-config libusb-1.0 --libs --cflags`

its result is that -I/usr/include/libusb-1.0 -lusb-1.0

C++ Redefinition Header Files (winsock2.h)

In my project (I use VS 2008 SP1) works next solution:

Header file:

//myclass.h
#pragma once
#define _WINSOCKAPI_
#include <windows.h>

Cpp class:

//myclass.cpp
#include "Util.h"
#include "winsock2class.h"
#pragma comment(lib, "Ws2_32.lib")

where #include "winsock2class.h" mean class which implemented winsock2.h :

//winsock2class.h
#include <winsock2.h>
#include <windows.h>
#pragma comment(lib, "Ws2_32.lib")

How to loop through Excel files and load them into a database using SSIS package?

I ran into an article that illustrates a method where the data from the same excel sheet can be imported in the selected table until there is no modifications in excel with data types.

If the data is inserted or overwritten with new ones, importing process will be successfully accomplished, and the data will be added to the table in SQL database.

The article may be found here: http://www.sqlshack.com/using-ssis-packages-import-ms-excel-data-database/

Hope it helps.

How to know the git username and email saved during configuration?

Inside your git repository directory, run git config user.name.

Why is running this command within your git repo directory important?

If you are outside of a git repository, git config user.name gives you the value of user.name at global level. When you make a commit, the associated user name is read at local level.

Although unlikely, let's say user.name is defined as foo at global level, but bar at local level. Then, when you run git config user.name outside of the git repo directory, it gives bar. However, when you really commits something, the associated value is foo.


Git config variables can be stored in 3 different levels. Each level overrides values in the previous level.

1. System level (applied to every user on the system and all their repositories)

  • to view, git config --list --system (may need sudo)
  • to set, git config --system color.ui true
  • to edit system config file, git config --edit --system

2. Global level (values specific personally to you, the user. )

  • to view, git config --list --global
  • to set, git config --global user.name xyz
  • to edit global config file, git config --edit --global

3. Repository level (specific to that single repository)

  • to view, git config --list --local
  • to set, git config --local core.ignorecase true (--local optional)
  • to edit repository config file, git config --edit --local (--local optional)

How to view all settings?

  • Run git config --list, showing system, global, and (if inside a repository) local configs
  • Run git config --list --show-origin, also shows the origin file of each config item

How to read one particular config?

  • Run git config user.name to get user.name, for example.
  • You may also specify options --system, --global, --local to read that value at a particular level.

Reference: 1.6 Getting Started - First-Time Git Setup

correct configuration for nginx to localhost?

Fundamentally you hadn't declare location which is what nginx uses to bind URL with resources.

 server {
            listen       80;
            server_name  localhost;

            access_log  logs/localhost.access.log  main;

            location / {
                root /var/www/board/public;
                index index.html index.htm index.php;
            }
       }

Inserting multiple rows in mysql

Here is a PHP solution ready for use with a n:m (many-to-many relationship) table :

// get data
$table_1 = get_table_1_rows();
$table_2_fk_id = 123;

// prepare first part of the query (before values)
$query = "INSERT INTO `table` (
   `table_1_fk_id`,
   `table_2_fk_id`,
   `insert_date`
) VALUES ";

//loop the table 1 to get all foreign keys and put it in array
foreach($table_1 as $row) {
    $query_values[] = "(".$row["table_1_pk_id"].", $table_2_fk_id, NOW())";
}

// Implode the query values array with a coma and execute the query.
$db->query($query . implode(',',$query_values));

How to use order by with union all in sql?

You don't really need to have parenthesis. You can sort directly:

SELECT *, 1 AS RN FROM TABLE_A
UNION ALL 
SELECT *, 2 AS RN FROM TABLE_B
ORDER BY RN, COLUMN_1

Selection with .loc in python

This is using dataframes from the pandas package. The "index" part can be either a single index, a list of indices, or a list of booleans. This can be read about in the documentation: https://pandas.pydata.org/pandas-docs/stable/indexing.html

So the index part specifies a subset of the rows to pull out, and the (optional) column_name specifies the column you want to work with from that subset of the dataframe. So if you want to update the 'class' column but only in rows where the class is currently set as 'versicolor', you might do something like what you list in the question:

iris_data.loc[iris_data['class'] == 'versicolor', 'class'] = 'Iris-versicolor'

await is only valid in async function

If you are writing a Chrome Extension and you get this error for your code at root, you can fix it using the following "workaround":

async function run() {
    // Your async code here
    const beers = await fetch("https://api.punkapi.com/v2/beers");
}

run();

Basically you have to wrap your async code in an async function and then call the function without awaiting it.

IntelliJ: Error:java: error: release version 5 not supported

Took me a while to aggregate an actual solution, but here's how to get rid of this compile error.

  1. Open IntelliJ preferences.

  2. Search for "compiler" (or something like "compi").

  3. Scroll down to Maven -->java compiler. In the right panel will be a list of modules and their associated java compile version "target bytecode version."

  4. Select a version >1.5. You may need to upgrade your jdk if one is not available.

enter image description here

Where/How to getIntent().getExtras() in an Android Fragment?

you can still use

String Item = getIntent().getExtras().getString("name");

in the fragment, you just need call getActivity() first:

String Item = getActivity().getIntent().getExtras().getString("name");

This saves you having to write some code.

Semaphore vs. Monitors - what's the difference?

A Monitor is an object designed to be accessed from multiple threads. The member functions or methods of a monitor object will enforce mutual exclusion, so only one thread may be performing any action on the object at a given time. If one thread is currently executing a member function of the object then any other thread that tries to call a member function of that object will have to wait until the first has finished.

A Semaphore is a lower-level object. You might well use a semaphore to implement a monitor. A semaphore essentially is just a counter. When the counter is positive, if a thread tries to acquire the semaphore then it is allowed, and the counter is decremented. When a thread is done then it releases the semaphore, and increments the counter.

If the counter is already zero when a thread tries to acquire the semaphore then it has to wait until another thread releases the semaphore. If multiple threads are waiting when a thread releases a semaphore then one of them gets it. The thread that releases a semaphore need not be the same thread that acquired it.

A monitor is like a public toilet. Only one person can enter at a time. They lock the door to prevent anyone else coming in, do their stuff, and then unlock it when they leave.

A semaphore is like a bike hire place. They have a certain number of bikes. If you try and hire a bike and they have one free then you can take it, otherwise you must wait. When someone returns their bike then someone else can take it. If you have a bike then you can give it to someone else to return --- the bike hire place doesn't care who returns it, as long as they get their bike back.

Run PHP Task Asynchronously

PHP HAS multithreading, its just not enabled by default, there is an extension called pthreads which does exactly that. You'll need php compiled with ZTS though. (Thread Safe) Links:

Examples

Another tutorial

pthreads PECL Extension

Eclipse does not start when I run the exe?

Try to install Eclipse into a folder without spaces.

How to add constraints programmatically using Swift

the following code works for me in this scenario: an UIImageView forced landscape.

    imagePreview!.isUserInteractionEnabled = true
    imagePreview!.isExclusiveTouch = true
    imagePreview!.contentMode = UIView.ContentMode.scaleAspectFit
    
    // Remove all constraints
    imagePreview!.removeAllConstraints()
    
    // Add the new constraints
    let guide = view.safeAreaLayoutGuide
    imagePreview!.translatesAutoresizingMaskIntoConstraints = false
    imagePreview!.leadingAnchor.constraint(equalTo: guide.leadingAnchor).isActive = true
    imagePreview!.trailingAnchor.constraint(equalTo: guide.trailingAnchor).isActive = true
    imagePreview!.heightAnchor.constraint(equalTo: guide.heightAnchor, multiplier: 1.0).isActive = true

where removeAllConstraints is an extension

extension UIView {
    
    func removeAllConstraints() {
        var _superview = self.superview
        
        func removeAllConstraintsFromView(view: UIView) { for c in view.constraints { view.removeConstraint(c) } }
        
        while let superview = _superview {
            for constraint in superview.constraints {
                
                if let first = constraint.firstItem as? UIView, first == self {
                    superview.removeConstraint(constraint)
                }
                
                if let second = constraint.secondItem as? UIView, second == self {
                    superview.removeConstraint(constraint)
                }
            }
            
            _superview = superview.superview
        }
        
        self.removeConstraints(self.constraints)
        self.translatesAutoresizingMaskIntoConstraints = true
    }
}

When should I really use noexcept?

In Bjarne's words (The C++ Programming Language, 4th Edition, page 366):

Where termination is an acceptable response, an uncaught exception will achieve that because it turns into a call of terminate() (§13.5.2.5). Also, a noexcept specifier (§13.5.1.1) can make that desire explicit.

Successful fault-tolerant systems are multilevel. Each level copes with as many errors as it can without getting too contorted and leaves the rest to higher levels. Exceptions support that view. Furthermore, terminate() supports this view by providing an escape if the exception-handling mechanism itself is corrupted or if it has been incompletely used, thus leaving exceptions uncaught. Similarly, noexcept provides a simple escape for errors where trying to recover seems infeasible.

double compute(double x) noexcept;     {
    string s = "Courtney and Anya";
    vector<double> tmp(10);
    // ...
}

The vector constructor may fail to acquire memory for its ten doubles and throw a std::bad_alloc. In that case, the program terminates. It terminates unconditionally by invoking std::terminate() (§30.4.1.3). It does not invoke destructors from calling functions. It is implementation-defined whether destructors from scopes between the throw and the noexcept (e.g., for s in compute()) are invoked. The program is just about to terminate, so we should not depend on any object anyway. By adding a noexcept specifier, we indicate that our code was not written to cope with a throw.

How can I detect browser type using jQuery?

I have used this and it works for me.Also include jquery migrate plugin,and jquery file.

if ( $.browser.webkit ) {
alert( "This is WebKit!" );
}

What's the name for hyphen-separated case?

Here is a more recent discombobulation. Documentation everywhere in angular JS and Pluralsight courses and books on angular, all refer to kebab-case as snake-case, not differentiating between the two.

Its too bad caterpillar-case did not stick because snake_case and caterpillar-case are easily remembered and actually look like what they represent (if you have a good imagination).

Check if element found in array c++

There are many ways...one is to use the std::find() algorithm, e.g.

#include <algorithm>

int myArray[] = { 3, 2, 1, 0, 1, 2, 3 };
size_t myArraySize = sizeof(myArray) / sizeof(int);
int *end = myArray + myArraySize;
// find the value 0:
int *result = std::find(myArray, end, 0);
if (result != end) {
  // found value at "result" pointer location...
}

C# importing class into another class doesn't work

MyClass is a class not a namespace. So this code is wrong:

using MyClass //THIS CODE IS NOT CORRECT

You should check the namespace of the MyClass (e.g: MyNamespace). Then call it in a proper way:

MyNamespace.MyClass myClass =new MyNamespace.MyClass();

Saving results with headers in Sql Server Management Studio

At least in SQL Server 2012, you can right click in the query window and select Query Options. From there you can select Include Headers for grid and/or text and have the Save As work the way you want it without restarting SSMS.

You'll still need to change it in Tools->Options in the menu bar to have new query windows use those settings by default.

How to read and write excel file

If column number are varing you can use this

package com.org.tests;
import org.apache.poi.xssf.usermodel.*;
import java.io.FileInputStream;
import java.io.IOException;

public class ExcelSimpleTest 
{   
    String path;
    public FileInputStream fis = null;
    private XSSFWorkbook workbook = null;
    private XSSFSheet sheet = null;
    private XSSFRow row   =null;
    private XSSFCell cell = null;

    public ExcelSimpleTest() throws IOException
    {
        path = System.getProperty("user.dir")+"\\resources\\Book1.xlsx";
        fis = new FileInputStream(path); 
        workbook = new XSSFWorkbook(fis);
        sheet = workbook.getSheetAt(0);
    }
    public void ExelWorks()
    {
        int index = workbook.getSheetIndex("Sheet1");
        sheet = workbook.getSheetAt(index);
        int rownumber=sheet.getLastRowNum()+1;  

        for (int i=1; i<rownumber; i++ )
        {
            row = sheet.getRow(i);
            int colnumber = row.getLastCellNum();
            for (int j=0; j<colnumber; j++ )
            {
                cell = row.getCell(j);
                System.out.println(cell.getStringCellValue());
            }
        }
    }   
    public static void main(String[] args) throws IOException 
    {
        ExcelSimpleTest excelwork = new ExcelSimpleTest();
        excelwork.ExelWorks();
    }
}

The corresponding mavendependency can be found here

Change span text?

Replace whatever is in the address bar with this:

javascript:document.getElementById('serverTime').innerHTML='[text here]';

Example.

how to console.log result of this ajax call?

$.ajax({
    type: 'POST',
    url: 'loginCheck',
    data: $(formLogin).serialize(),    
    success: function(result){
        console.log('my message' + result);
    }
});

How to copy a huge table data into another table in SQL Server

Here's another way of transferring large tables. I've just transferred 105 million rows between two servers using this. Quite quick too.

  1. Right-click on the database and choose Tasks/Export Data.
  2. A wizard will take you through the steps but you choosing your SQL server client as the data source and target will allow you to select the database and table(s) you wish to transfer.

For more information, see https://www.mssqltips.com/sqlservertutorial/202/simple-way-to-export-data-from-sql-server/

When to use HashMap over LinkedList or ArrayList and vice-versa

Lists represent a sequential ordering of elements. Maps are used to represent a collection of key / value pairs.

While you could use a map as a list, there are some definite downsides of doing so.

Maintaining order: - A list by definition is ordered. You add items and then you are able to iterate back through the list in the order that you inserted the items. When you add items to a HashMap, you are not guaranteed to retrieve the items in the same order you put them in. There are subclasses of HashMap like LinkedHashMap that will maintain the order, but in general order is not guaranteed with a Map.

Key/Value semantics: - The purpose of a map is to store items based on a key that can be used to retrieve the item at a later point. Similar functionality can only be achieved with a list in the limited case where the key happens to be the position in the list.

Code readability Consider the following examples.

    // Adding to a List
    list.add(myObject);         // adds to the end of the list
    map.put(myKey, myObject);   // sure, you can do this, but what is myKey?
    map.put("1", myObject);     // you could use the position as a key but why?

    // Iterating through the items
    for (Object o : myList)           // nice and easy
    for (Object o : myMap.values())   // more code and the order is not guaranteed

Collection functionality Some great utility functions are available for lists via the Collections class. For example ...

    // Randomize the list
    Collections.shuffle(myList);

    // Sort the list
    Collections.sort(myList, myComparator);  

Hope this helps,

How to get distinct results in hibernate with joins and row-based limiting (paging)?

A slight improvement building on FishBoy's suggestion.

It is possible to do this kind of query in one hit, rather than in two separate stages. i.e. the single query below will page distinct results correctly, and also return entities instead of just IDs.

Simply use a DetachedCriteria with an id projection as a subquery, and then add paging values on the main Criteria object.

It will look something like this:

DetachedCriteria idsOnlyCriteria = DetachedCriteria.forClass(MyClass.class);
//add other joins and query params here
idsOnlyCriteria.setProjection(Projections.distinct(Projections.id()));

Criteria criteria = getSession().createCriteria(myClass);
criteria.add(Subqueries.propertyIn("id", idsOnlyCriteria));
criteria.setFirstResult(0).setMaxResults(50);
return criteria.list();

How can I find the length of a number?

var x = 1234567;

x.toString().length;

This process will also work forFloat Number and for Exponential number also.

What is the difference between a pandas Series and a single-column DataFrame?

from the pandas doc http://pandas.pydata.org/pandas-docs/stable/dsintro.html Series is a one-dimensional labeled array capable of holding any data type. To read data in form of panda Series:

import pandas as pd
ds = pd.Series(data, index=index)

DataFrame is a 2-dimensional labeled data structure with columns of potentially different types.

import pandas as pd
df = pd.DataFrame(data, index=index)

In both of the above index is list

for example: I have a csv file with following data:

,country,popuplation,area,capital
BR,Brazil,10210,12015,Brasile
RU,Russia,1025,457,Moscow
IN,India,10458,457787,New Delhi

To read above data as series and data frame:

import pandas as pd
file_data = pd.read_csv("file_path", index_col=0)
d = pd.Series(file_data.country, index=['BR','RU','IN'] or index =  file_data.index)

output:

>>> d
BR           Brazil
RU           Russia
IN            India

df = pd.DataFrame(file_data.area, index=['BR','RU','IN'] or index = file_data.index )

output:

>>> df
      area
BR   12015
RU     457
IN  457787

bootstrap 4 file input doesn't show the file name

This works with Bootstrap 4.1.3:

<script>
    $("input[type=file]").change(function () {
        var fieldVal = $(this).val();

        // Change the node's value by removing the fake path (Chrome)
        fieldVal = fieldVal.replace("C:\\fakepath\\", "");

        if (fieldVal != undefined || fieldVal != "") {
            $(this).next(".custom-file-label").attr('data-content', fieldVal);
            $(this).next(".custom-file-label").text(fieldVal);
        }
    });
</script>

org.springframework.web.client.HttpClientErrorException: 400 Bad Request

This is what worked for me. Issue is earlier I didn't set Content Type(header) when I used exchange method.

MultiValueMap<String, String> map = new LinkedMultiValueMap<String, String>();
map.add("param1", "123");
map.add("param2", "456");
map.add("param3", "789");
map.add("param4", "123");
map.add("param5", "456");

HttpHeaders headers = new HttpHeaders();
headers.setContentType(MediaType.APPLICATION_FORM_URLENCODED);

final HttpEntity<MultiValueMap<String, String>> entity = new HttpEntity<MultiValueMap<String, String>>(map ,
        headers);
JSONObject jsonObject = null;

try {
    RestTemplate restTemplate = new RestTemplate();
    ResponseEntity<String> responseEntity = restTemplate.exchange(
            "https://url", HttpMethod.POST, entity,
            String.class);

    if (responseEntity.getStatusCode() == HttpStatus.CREATED) {
        try {
            jsonObject = new JSONObject(responseEntity.getBody());
        } catch (JSONException e) {
            throw new RuntimeException("JSONException occurred");
        }
    }
  } catch (final HttpClientErrorException httpClientErrorException) {
        throw new ExternalCallBadRequestException();
  } catch (HttpServerErrorException httpServerErrorException) {
        throw new ExternalCallServerErrorException(httpServerErrorException);
  } catch (Exception exception) {
        throw new ExternalCallServerErrorException(exception);
    } 

ExternalCallBadRequestException and ExternalCallServerErrorException are the custom exceptions here.

Note: Remember HttpClientErrorException is thrown when a 4xx error is received. So if the request you send is wrong either setting header or sending wrong data, you could receive this exception.

How to hide a mobile browser's address bar?

In my case problem was in css and html layout. Layout was something like html - body - root - ... html and body was overflow: hidden, and root was position: fixed, height: 100vh.

Whith this layout browser tabs on mobile doesnt hide. For solve this I delete overflow: hidden from html and body and delete position: fixed, height: 100vh from root.

Why doesn't wireshark detect my interface?

This is usually caused by incorrectly setting up permissions related to running Wireshark correctly. While you can avoid this issue by running Wireshark with elevated privileges (e.g. with sudo), it should generally be avoided (see here, specifically here). This sometimes results from an incomplete or partially successful installation of Wireshark. Since you are running Ubuntu, this can be resolved by following the instructions given in this answer on the Wireshark Q&A site. In summary, after installing Wireshark, execute the following commands:

sudo dpkg-reconfigure wireshark-common 
sudo usermod -a -G wireshark $USER

Then log out and log back in (or reboot), and Wireshark should work correctly without needing additional privileges. Finally, if the problem is still not resolved, it may be that dumpcap was not correctly configured, or there is something else preventing it from operating correctly. In this case, you can set the setuid bit for dumpcap so that it always runs as root.

sudo chmod 4711 `which dumpcap`

One some distros you might get the following error when you execute the command above:

chmod: missing operand after ‘4711’

Try 'chmod --help' for more information.

In this case try running

sudo chmod 4711 `sudo which dumpcap`

How to display count of notifications in app launcher icon

It works in samsung touchwiz launcher

public static void setBadge(Context context, int count) {
    String launcherClassName = getLauncherClassName(context);
    if (launcherClassName == null) {
        return;
    }
    Intent intent = new Intent("android.intent.action.BADGE_COUNT_UPDATE");
    intent.putExtra("badge_count", count);
    intent.putExtra("badge_count_package_name", context.getPackageName());
    intent.putExtra("badge_count_class_name", launcherClassName);
    context.sendBroadcast(intent);
}

public static String getLauncherClassName(Context context) {

    PackageManager pm = context.getPackageManager();

    Intent intent = new Intent(Intent.ACTION_MAIN);
    intent.addCategory(Intent.CATEGORY_LAUNCHER);

    List<ResolveInfo> resolveInfos = pm.queryIntentActivities(intent, 0);
    for (ResolveInfo resolveInfo : resolveInfos) {
        String pkgName = resolveInfo.activityInfo.applicationInfo.packageName;
        if (pkgName.equalsIgnoreCase(context.getPackageName())) {
            String className = resolveInfo.activityInfo.name;
            return className;
        }
    }
    return null;
}