1name,age
2Alice-Alice,30
3Bob,25
4Charlie,35

lower & lower_#

lowercase the string and lower_ will lowercase the string in place.

1filterx csv test.csv -e -H --oH 'lower_(name)'
2
3### Output
4name,age
5alice-alice,30
6bob,25
7charlie,35

upper & upper_#

same as lower but for uppercase.

replace & replace_#

replace will replace all occurrences of a substring with another substring, while replace_ will replace in place.

1filterx csv test.csv -e -H --oH 'replace(name, "Alice", "lady")'
2
3### Output
4name,age
5lady-lady,30
6Bob,25
7Charlie,35

replace_one & replace_one_#

same as replace but only replaces the first occurrence.

1filterx csv test.csv -e -H --oH 'replace_one(name, "Alice", "lady")'
2
3### Output
4name,age
5lady-Alice,30
6Bob,25
7Charlie,35

slice & slice_#

get a slice of the string, slice will return a new string while slice_ will modify the string in place.

slice assumes 0-based indexing, so slice(name, 3) will return string from 0 with length 3. slice(name, 3, 2) will return string from 3 with length 2.

1filterx csv test.csv -e -H --oH 'slice(name, 3)'
2### Output
3name,age
4Ali,30
5Bob,25
6Cha,35

it also supports (start, length) syntax.

1filterx csv test.csv -e -H --oH 'slice(name, 3, 2)'
2### Output
3name,age
4ce,30
5ob,25
6rl,35

strip & strip_#

remove leading and trailing string, strip will return a new string while strip_ will modify the string in place.

1a
2applepleap
3oommmoo

1filterx csv strip.csv -e -H --oH 'strip_(a, "ap")'
2
3### Output
4a
5pleple
6oommmoo

lstrip & lstrip_#

same as strip but only remove leading string.

rstrip & rstrip_#

same as strip but only remove trailing string.

len#

returns the length of the string.

1filterx csv test.csv -e -H --oH 'alias(len) = len(name)'
2
3### Output
4name,age,len
5Alice-Alice,30,11
6Bob,25,3
7Charlie,35,7