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Python
Arrays
Functions
Regex
Strings
Create / delete
Initialise
Count
Retrieve by index
Slice
Compare
Search
Split
Iterate
Evaluate
Print
Insert
Overwrite
Replace
Remove by value
Remove by index
Trim
Sort
Convert case
Python Strings
Create / delete
Create string a=""
a="abcdef"
abcdef
Initialise
Fixed contents a=""
a="abcdef";
abcdef
Repeated value 'x' x 10 c='x'
a=c*10
xxxxxxxxxx
Count
Length of string a="abc"
i=len(a)
3
Number of 'X' chars in string a="abcXdefXX"
n=a.count('X')
3
Number of 'X', 'Y' and 'Z' chars in string a="abcXdefYZ"
n=a.count('X')+a.count('Y')+a.count('Z')
3
Number of 'abc' substrings in string a="abcabcdefabc"
n=a.count('abc')
3
Retrieve by index
Retrieve 1st char a="abc";
c=a[0]
a
Retrieve last char a="abc";
c=a[-1]
c
Retrieve char 'n' a="abcdef";
n=2;
c=a[n]
c
Retrieve out-of-bounds char a="abc"; n=4
try:
  c=a[n]
except:
  c="out of range"
out of range
Slice
Slice from index 'm' to 'n' (inclusive) a="abcdefghi";
m=3;
n=6;
s=a[m:n+1]
defg
Slice from index 'n' (inclusive) a="abcdefghi";
n=3;
s=a[n:]
defghi
Slice up to index 'n' (inclusive) a="abcdefghi";
n=3;
s=a[:n+1]
abcd
Compare
Test for equality (case sensitive) a="abcdef";
b="abc";
t=(a==b)
0
Test for equality (case insensitive) a="abcdef";
b="ABCdef";
t=(a.lower() == b.lower())
1
Test for equality (case insensitive) [alternative] a="abcdef";
b="ABCdef";
t=(re.match("^"+a+"$", b, re.IGNORECASE)!=None)
1
Test for prefix a="abcdef";
b="abc";
t=a.startswith(b)
1
Test for prefix [alternative] a="abcdef";
b="abc";
t=(re.match("^"+b+".*",a)!=None)
1
Test for suffix a="abcdef";
b="def";
t=a.endswith(b)
1
Test for suffix [alternative] a="abcdef";
b="def";
t=(re.match(".*"+b+"$",a)!=None)
1
Search
Test char 'is in' string a="abcdefghi";
c='c';
t=(string.find(a,c) != -1)
1
Test substring 'is in' string a="abcdefghi";
b="abc";
t=(string.find(a,b) != -1)
1
Find first occurrence of char a="abcdefccccc";
c='c';
i=string.index(a,c)
2
Find last occurrence of char a="abcdefccccc";
c='c';
i=string.rindex(a,c)
10
Find first occurrence of string a="abcdefabc";
b="abc";
i=string.index(a,b)
0
Find last occurrence of string a="abcdefabc";
b="abc";
i=string.rindex(a,b)
6
Split
Split on char a="one,two,three";
c=',';
sa=string.split(a,c)
one two three
Split on string a="aa_x_bb_x_cc";
b="_x_";a
sa=string.split(a,b)
aa bb cc
Split limited to 'n' parts a="one,two,three";
c=',';
n=2;
sa=string.split(a,c,n-1)
one two,three
Iterate
Iterate through string a="abcdef";
b=""
for x in a:
  b=(b+x+',')
a,b,c,d,e,f,
Evaluate
Evaluate empty string a=""
t=0
if a:
  t=1
0
Evaluate non-empty string a="abcdef"
t=0
if a:
  t=1
1
Print
Basic printing a="abcdef"
print a
abcdef
Formatting sprintf style a="abc";
b="abcdef"
s="%10s %10s" % ( a, b )
       abc abcdef
Insert
Prepend char a="bcdef";
c='a';
a=c+a
abcdef
Append char a="abc";
c='d';
a=a+c
abcd
Insert char at index 'n' a="abc";
c='X';
n=1;
a=a[:n]+c+a[n:]
aXbc
Prepend string a="def"
b="abc"
a=b+a
abcdef
Append string a="abc"
b="def"
a=a+b
abcdef
Insert string at index 'n' a="abcghi";
b="def";
n=3;
a=a[:n]+b+a[n:]
abcdefghi
Concatenate 'a' and 'b' a="abc";
b="def";
s=a+b
abcdef
Overwrite
Overwrite char at index 'n' a="abc";
n=1;
c='B';
ca=array('c');
ca.fromstring(a);
ca[n]='B';
a=ca.tostring()
aBc
Overwrite substring at index 'n' a="abcdefghi"
b="DEF"
n=3
a=a[:n]+b+a[n+len(b):]
abcDEFghi
Replace
Replace 1st instance of char 'X' with 'Y' a="XXXYYYZZZ"
a=a.replace('X','Y',1)
YXXYYYZZZ
Replace all instances of char 'X' with 'Y' a="XXXYYYZZZ";
a=a.replace('X','Y')
YYYYYYZZZ
Replace 1st instance of substring 'abc' with 'XYZ' a="abcdefabc"
a=a.replace("abc","XYZ",1)
XYZdefabc
Replace all instances of substring 'abc' with 'XYZ' a="abcdefabc"
a=a.replace("abc","XYZ")
XYZdefXYZ
Replace all instances of 'X','Y','Z' with 'A','B','C' respectively a="XXXYYYZZZ";
a=a.replace('X','A').replace('Y','B').replace('Z','C')
AAABBBCCC
Remove by value
Remove 1st instance of char 'X' a="XXXYYYZZZ"
a=a.replace('X','',1)
XXYYYZZZ
Remove all instances of char 'X' a="XXXYYYZZZ"
a=a.replace('X','')
YYYZZZ
Remove 1st instance of substring 'abc' a="abcdefabc"
a=a.replace("abc","",1)
defabc
Remove all instances of substring 'abc' a="abcdefabc"
a=a.replace("abc","")
def
Remove prefix 'abc.' a="abc.abc.def"
a=re.sub(r"^abc.","",a)
abc.def
Remove suffix '.def' a="abc.def.def"
a=re.sub(r"\.def$","",a)
abc.def
Remove by index
Remove 1st char a="abcdef";
a=a[1:]
bcdef
Remove last char a="abcdefghi";
a=a[:-1]
abcdefgh
Remove char at index 'n' a="abcdef";
n=3;
a=a[:n]+a[n+1:]
abcef
Remove chars in index range 'm' to 'n' (inclusive) a="abcdef";
m=2;
n=4;
a=a[:m]+a[n+1:]
abf
Remove chars from index 'n' onwards (inclusive) a="abcdefghi";
n=3;
a=a[:n]
abc
Remove chars up to index 'n' (inclusive) a="abcdefghi";
n=3;
a=a[n+1:]
efghi
Trim
Trim leading white space a=" abc def "
a=string.lstrip(a)
abc def
Trim trailing white space a=" abc def "
a=string.rstrip(a)
   abc def
Trim leading and trailing white space a=" abc def "
a=string.strip(a)
abc def
Trim trailing carriage return a="abcdef\n"
a=string.strip(a)
abcdef
Sort
Sort in ascending order a="cafdeb";
am=map(None,a);
am.sort();
a=string.join(am,"")
abcdef
Sort in descending order a="cafdeb";
am=map(None,a);
am.sort();
am.reverse();
a=string.join(am,"")
fedcba
Sort in custom order a="cafdeb";
def comp(x,y):
  return ord(y)-ord(x)
am=map(None,a);
am.sort(comp);
a=string.join(am,"")
fedcba
Reverse a="abcdefghi";
aa=array('c',a);
aa.reverse();
a=string.join(aa,"")
ihgfedcba
Convert case
Convert to lower case a="ABCDEFGHI";
a=a.lower()
abcdefghi
Convert to upper case a="abcdefghi";
a=a.upper()
ABCDEFGHI
Convert first char to lower case a="ABCDEFGHI";
a=a[0].lower()+a[1:]
aBCDEFGHI
Convert first char to upper case a="abcdefghi";
a=a.capitalize()
Abcdefghi