Chess Misc

position_eval.py

This is a command line tool for quickly evaluating a position in chess.

Here are the basics you need to know to get started :

* **Input** : Any FEN string(s) or a file containing FENs

>> python position_eval.py <fen1> [<fen2>...<fenN>]

>> python position_eval.py file <filename>

(Note : filename must have the extension .fen)

```

* **Output** : Current evaluation score and the best move. The FEN(s) along with the evaluation score is also written to a file called *game_moves.log*

plotter.py

You can also plot evaluation score vs number of moves using

>> python plotter.py

This will take data from *game_moves.log*

make_dataset.py

This file takes in a puzzle file in PGN format which contains Mate in 4+ puzzles, parses out the FEN strings, finds the optimal move sequence for mate and prints it to `stdout` and a file named `dataset`

import re

import matplotlib.pyplot as plt

def main() :

with open('./game_moves.log', 'r') as f:

read_data = f.readlines()

f.close()

moves = []

change_eval = []

num_moves = 0

for s in read_data :

split = s.split("[")

change_eval.append(int(re.match(r'-?\d+', split[1]).group()))

num_moves += 1

for x in range(0,num_moves):

moves.append(x)

print moves

print change_eval

plt.plot(moves, change_eval)

plt.ylabel('change in eval score')

plt.xlabel('move number')

# plt.xlim([0,20])

# plt.ylim([-5000,5000])

plt.show()

main()

import sys

import subprocess, time

engine = subprocess.Popen(

'./stockfish',

universal_newlines=True,

stdin=subprocess.PIPE,

stdout=subprocess.PIPE,

)

def put(command):

engine.stdin.write(command+'\n')

def get():

# using the 'isready' command (engine has to answer 'readyok')

# to indicate current last line of stdout

eval_score = ''

bestmove = ''

engine.stdin.write('isready\n')

while True:

text = engine.stdout.readline().strip()

if text == 'readyok':

break

elif text != '' and text.startswith('info depth'):

eval_score = text.split()[7]

elif text != '' and text.startswith('bestmove'):

bestmove = text.split()[1]

return float(eval_score), bestmove

def get_score(fen):

put('position fen ' + fen)

put('go movetime 1000')

time.sleep(1.2)

if __name__ == "__main__":

if len(sys.argv) < 2:

print 'Atleast one FEN must be provided'

sys.exit()

args = sys.argv

del args[0]

if(args[0] == 'file'):

if(len(args) < 2):

print 'Please enter a filename'

sys.exit()

else:

with open(args[1]) as f:

content = f.readlines()

args = content

f = open('game_moves.log','w')

for fen in args:

# 8/6pk/8/1R5p/3K3P/8/6r1/8 b - - 0 42

# fen = fen.split('[')[0]

fen = fen.strip()

get_score(fen)

data = get()

print data

string = fen + "[" + str(data[0]) + "]\n"

f.write(string)

f.close();

put('quit')