str_float

str_float{s:str, f:float, format:str, default:float}

A relation generator. Can convert string s into float f and vice-versa.

For each string that cannot be parsed, no tuple is returned.

If format is given it is treated as a format string. See print for details.

If default is given it is used for f when s is "".

Examples

string to float

str_float(s:="3.142")

f
format
default

3.142
0

float to string

str_float(f:=42.0)

s
format
default

42
0

float with format

str_float(f:=3.14159, format:=":.3f")

s
default

3.142
0

bulk operation - with some invalid and some empty

d := {s:str}{
     ["3.142"]
     ["not a float"]
     [""]
     ["99"]
     ["-42"]
}
(d & str_float){s, f}

┌───────┬────────┐
│ s     │ f      │
├───────┼────────┤
│       │   0.00 │
│ -42   │ -42.00 │
│ 3.142 │   3.14 │
│ 99    │  99.00 │
└───────┴────────┘