json モジュール (2) ( json__formulaParser.py )¶
数式処理 json5 parser コマンド¶
json5にて、 数式処理 をできるようにしたpython json5 parser.
ルール¶
文字列を与えた際は、常に、try する．
一方で、普通の文字列との区別がつかないので、エラーはでない．
エラーをだすには オプショナル引数として、"verbose=True" を与える．
または、数式は文字式で与え、文字式内にバッククォートで囲まれた領域を持つものとする
formula_mark=" ` "として与える．
" ` (数式) ` " という構成．
バッククォート前後の空白は許すが、空白以外があると感知されない．
正規表現的には、 r"\s*`([\s\S]+)`\s*"
引数のexpr_fmlで正規表現を与えれば、 変更も可能 ．
変数は"変数マークをつけた語"で記載．（e.g. ${...} ：ShellScript 環境変数 -like）
前後での空白は許すが、括弧内や＄マークとの間の空白は許さない
｛｝はあってもなくてもよい．
正規表現例(@のとき)： "@\{*[varname]\}*\s*" ( [varname] は登録変数名、総当りで検索． )
その他、空白は許されるはず．
変数名に 正規表現でエスケープが必要となる文字 を使用する際は注意（ "."など．）
parser 関数( コード )¶
import json5, re, math, sys, decimal
import numpy as np
# ========================================================= #
# === json__formulaParser.py === #
# ========================================================= #
def json__formulaParser( inpFile=None, stop__error=False, verbose=False, table=None, \
expr_fml=None, formula_mark="", variable_mark="$", iterMax=10 ):
if ( expr_fml is None ):
if ( formula_mark == "`" ):
expr_fml = r"\s*`([\s\S]+)`\s*"
elif ( formula_mark == "" ):
expr_fml = r"([\s\S]+)"
else:
print( "[json__formulaParser.py] formula_mark == {} ??? ".format( variable_mark ) )
sys.exit()
if ( variable_mark in [ "$" ] ):
variable_mark = "\{}".format( variable_mark )
# ------------------------------------------------- #
# --- [1] load json file as json5 --- #
# ------------------------------------------------- #
with open( inpFile, "r" ) as f:
varDict = json5.load( f )
if ( table is not None ):
varDict = { **table, **varDict }
# ------------------------------------------------- #
# --- [2] convert formula string into value --- #
# ------------------------------------------------- #
for iloop in range( iterMax ):
updated = False
for key,val in varDict.items():
if ( type(val) is str ):
match_fml = re.match( expr_fml, val )
if ( match_fml ):
formula = match_fml.group(1)
for var_,val_ in varDict.items():
expr_from = variable_mark+"\{*"+var_+"\}*\s*"
expr_into = "{}".format( val_ )
formula = re.sub( expr_from, expr_into, formula )
try:
varDict[key] = eval( formula )
updated = True
except SyntaxError:
if ( verbose ):
print()
print( "[json__wformula.py] Cannot evaluate [ERROR]" )
print( "[json__wformula.py] key :: {}".format( key ) )
print( "[json__wformula.py] formula :: {}".format( val ) )
print( "[json__wformula.py] :: {}".format( formula ) )
print()
except:
if ( verbose ):
print()
print( "[json__wformula.py] Cannot evaluate [ERROR]" )
print( "[json__wformula.py] key :: {}".format( key ) )
print( "[json__wformula.py] formula :: {}".format( val ) )
print( "[json__wformula.py] :: {}".format( formula ) )
print()
raise
if not( updated ): break
# ------------------------------------------------- #
# --- [3] align__digits --- #
# ------------------------------------------------- #
for key,val in varDict.items():
if ( type(val) in [ int, np.int32 ] ):
varDict[key] = int( return__digitsAligned( val ) )
if ( type(val) in [ float, np.float64 ] ):
varDict[key] = float( return__digitsAligned( val ) )
if ( type(val) in [ list ] ):
stack = []
for vh in val:
if ( type(vh) in [ int, np.int32 ] ):
stack += [ int( return__digitsAligned( vh ) ) ]
elif ( type(vh) in [ float, np.float64 ] ):
stack += [ float( return__digitsAligned( vh ) ) ]
else:
stack += [ vh ]
varDict[key] = stack
# ------------------------------------------------- #
# --- [4] print parsed items --- #
# ------------------------------------------------- #
return( varDict )
def return__digitsAligned( value, maxDigit=8, precision=12 ):
if ( type( value ) in [ int, float, np.float64, np.int32 ] ):
decimal.getcontext().prec = precision
decimal.getcontext().rounding = decimal.ROUND_HALF_UP
exp = math.floor( math.log10( abs( value ) ) ) if ( value != 0 ) else 0.0
if ( abs( exp ) >= maxDigit ):
ret = ( "{:15." + str(maxDigit) + "e}" ).format( value )
else:
lowest = int( exp - maxDigit )
quant = decimal.Decimal( "1e{0}".format( lowest ) )
dval = decimal.Decimal.from_float( value ).quantize( quant )
ret = format(dval, "f").rstrip("0").rstrip(".")
return( ret )
else:
return( value )
# ========================================================= #
# === Execution of Pragram === #
# ========================================================= #
if ( __name__=="__main__" ):
# ------------------------------------------------- #
# --- [1] declare regexp and file name --- #
# ------------------------------------------------- #
inpFile = "test/json__formulaParser/sample1.json"
ret = json__formulaParser( inpFile=inpFile, variable_mark="$" )
print()
print( ret )
print()
# ------------------------------------------------- #
# --- [2] variable mark is "@" case --- #
# ------------------------------------------------- #
inpFile = "test/json__formulaParser/sample2.json"
ret = json__formulaParser( inpFile=inpFile, variable_mark="@" )
print()
print( ret )
print()
# ------------------------------------------------- #
# --- [2] variable mark is "@" case --- #
# ------------------------------------------------- #
inpFile = "test/json__formulaParser/sample3.json"
ret = json__formulaParser( inpFile=inpFile, variable_mark="@" )
print()
print( ret )
print()
{'string': 'This is a pen', 'val1': 30.0, 'val2': 2, 'arr1': [1.0, 2.0, 3.0], 'sw1': True, 'sw2': False, 'item': None, 'fml': 1.7320508075688774, 'fml2': 1.0000000000000002, 'val3': 60.0}
json サンプル¶
{
// This is a sample of json file
"string" :"This is a pen",
"val1" : 30.0,
"val2" : 2,
"arr1" : [1.0,2.0,3.0,],
"sw1" :true,
"sw2" :false,
"item" :null,
"fml" : " ` np.cos(${val1}/180.0*np.pi) * ${val2} ` ",
"fml2" : " ` np.cos(${val3}/180.0*np.pi) * ${val2} ` ",
"val3" : 60.0,
"val4" : " ` ${val1} + ${val2} ` ",
"val5" : " ` ${val3} * ${val4} ` ",
"val6" : " ` ${val5} / ${val1} ` ",
/* comment line */
}
