How to display multiple images in one figure correctly

Question

I am trying to display 20 random images on a single Figure  The images are indeed displayed  but they are overlaid  I am using   import numpy as np import matplotlib pyplot as plt w 10 h 10 fig plt figure   for i in range 1 20       img   np random randint 10  size  h w       fig add subplot i 2 1      plt imshow img  plt show     I would like them to appear naturally in a grid layout  say 4x5   each with the same size  Part of the problem is that I do not know what the arguments to add subplot mean  The documentation states that the arguments are the number of rows  number of columns  and plot number  There is no positioning argument  Additionally  the plot number can only be 1 or 2  How can I achieve this

User · Answer

You could try the following   import matplotlib pyplot as plt import numpy as np  def plot figures figures  nrows   1  ncols 1          Plot a dictionary of figures       Parameters     ----------     figures    lt title  figure gt  dictionary     ncols   number of columns of subplots wanted in the display     nrows   number of rows of subplots wanted in the figure              fig  axeslist   plt subplots ncols ncols  nrows nrows      for ind title in zip range len figures    figures           axeslist ravel   ind  imshow figures title   cmap plt jet            axeslist ravel   ind  set title title          axeslist ravel   ind  set axis off       plt tight layout     optional      generation of a dictionary of  title  images  number of im   20 w 10 h 10 figures     im  str i   np random randint 10  size  h w   for i in range number of im      plot of the images in a figure  with 5 rows and 4 columns plot figures figures  5  4   plt show     However  this is basically just copy and paste from here  Multiple figures in a single window for which reason this post should be considered to be a duplicate   I hope this helps

User · Answer

Here is my approach that you may try   import numpy as np import matplotlib pyplot as plt  w 10 h 10 fig plt figure figsize  8  8   columns   4 rows   5 for i in range 1  columns rows  1       img   np random randint 10  size  h w       fig add subplot rows  columns  i      plt imshow img  plt show     The resulting image      Original answer date  Oct 7  17 at 4 20   Edit 1  Since this answer is popular beyond my expectation  And I see that a small change is needed to enable flexibility for the manipulation of the individual plots  So that I offer this new version to the original code  In essence  it provides -   access to individual axes of subplots possibility to plot more features on selected axes subplot   New code   import numpy as np import matplotlib pyplot as plt  w   10 h   10 fig   plt figure figsize  9  13   columns   4 rows   5    prep  x y  for extra plotting xs   np linspace 0  2 np pi  60     from 0 to 2pi ys   np abs np sin xs               absolute of sine    ax enables access to manipulate each of subplots ax       for i in range columns rows       img   np random randint 10  size  h w         create subplot and append to ax     ax append  fig add subplot rows  columns  i 1        ax -1  set title  ax   str i      set title     plt imshow img  alpha 0 25     do extra plots on selected axes subplots   note  index starts with 0 ax 2  plot xs  3 ys  ax 19  plot ys  2  xs   plt show      finally  render the plot   The resulting plot     Edit 2  In the previous example  the code provides access to the sub-plots with single index  which is inconvenient when the figure has many rows columns of sub-plots  Here is an alternative of it  The code below provides access to the sub-plots with  row index  column index   which is more suitable for manipulation of array of many sub-plots   import matplotlib pyplot as plt import numpy as np    settings h  w   10  10          for raster image nrows  ncols   5  4    array of sub-plots figsize    6  8        figure size  inches    prep  x y  for extra plotting on selected sub-plots xs   np linspace 0  2 np pi  60     from 0 to 2pi ys   np abs np sin xs               absolute of sine    create figure  fig   and array of axes  ax  fig  ax   plt subplots nrows nrows  ncols ncols  figsize figsize     plot simple raster image on each sub-plot for i  axi in enumerate ax flat         i runs from 0 to  nrows ncols-1        axi is equivalent with ax rowid  colid      img   np random randint 10  size  h w       axi imshow img  alpha 0 25        get indices of row column     rowid   i    ncols     colid   i   ncols       write row col indices as axes  title for identification     axi set title  Row   str rowid     Col   str colid      one can access the axes by ax row id  col id    do additional plotting on ax row id  col id  of your choice ax 0  2  plot xs  3 ys  color  red   linewidth 3  ax 4  3  plot ys  2  xs  color  green   linewidth 3   plt tight layout True  plt show     The resulting plot

[matplotlib] How to display multiple images in one figure correctly?

Examples related to matplotlib