# Terminal visualization of 2D numpy arrays # Copyright (c) 2009 Nicolas P. Rougier # # This program is free software: you can redistribute it and/or modify it under # the terms of the GNU General Public License as published by the Free Software # Foundation, either version 3 of the License, or (at your option) any later # version. # # This program is distributed in the hope that it will be useful, but WITHOUT # ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS # FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. # # You should have received a copy of the GNU General Public License along with # this program. If not, see <http://www.gnu.org/licenses/>. # ------------------------------------------------------------------------------ """ Terminal visualization of 2D numpy arrays Using extended color capability of terminal (256 colors), the imshow function renders a 2D numpy array within terminal. """ import sys import numpy as np from matplotlib.cm import viridis def imshow (Z, vmin=None, vmax=None, cmap=viridis, show_cmap=True): ''' Show a 2D numpy array using terminal colors ''' Z = np.atleast_2d(Z) if len(Z.shape) != 2: print("Cannot display non 2D array") return vmin = vmin or Z.min() vmax = vmax or Z.max() # Build initialization string that setup terminal colors init = '' for i in range(240): v = i/240 r,g,b,a = cmap(v) init += "\x1b]4;%d;rgb:%02x/%02x/%02x\x1b\\" % (16+i, int(r*255),int(g*255),int(b*255)) # Build array data string data = '' for i in range(Z.shape[0]): for j in range(Z.shape[1]): c = 16 + int( ((Z[Z.shape[0]-i-1,j]-vmin) / (vmax-vmin))*239) if (c < 16): c=16 elif (c > 255): c=255 data += "\x1b[48;5;%dm " % c u = vmax - (i/float(max(Z.shape[0]-1,1))) * ((vmax-vmin)) if show_cmap: data += "\x1b[0m " data += "\x1b[48;5;%dm " % (16 + (1-i/float(Z.shape[0]))*239) data += "\x1b[0m %+.2f" % u data += "\n" sys.stdout.write(init+'\n') sys.stdout.write(data+'\n') if __name__ == '__main__': def func3(x,y): return (1- x/2 + x**5 + y**3)*np.exp(-x**2-y**2) dx, dy = .2, .2 x = np.arange(-3.0, 3.0, dx) y = np.arange(-3.0, 3.0, dy) X,Y = np.meshgrid(x, y) Z = np.array (func3(X, Y)) imshow (Z)