Show only decimals of float

Question

I need to print a float showing only the decimals of that float. For example:

1.23456 --> 23456
12.3456 --> 3456
123.456 --> 456

I've found the following solution:

float floatValue = 1.23455f;
String stringValue = Float.toString(floatValue);
int pointIndex = stringValue.indexOf(".");
String decimals = stringValue.substring(pointIndex + 1, stringValue.length() - 1);

But I think it's a little dirty and I wonder if there is any other standard way, using String.format or something similar. I did't find anything in the documentation. Thanks in advance!

You could always separate the fractional part of the float value and format it separately. But you'll still get the ".", I suspect. — Hot Licks, May 23 '14 at 11:55
@HotLicks That could very well give a completely different result - the fractional part of the `float` that represents a certain decimal most accurately may not be the same as the `float` that represents the fractional part of that decimal most accurately; because `float` variables are spaced differently depending on their magnitude. — Dawood ibn Kareem, May 23 '14 at 12:03
In fact I'm looking for a standard way, something like a formatter — jeojavi, May 23 '14 at 12:17
@DavidWallace - Well, the OP hasn't given us the standard "it rounds wrong" gripe yet, but I'm sure it's coming. — Hot Licks, May 23 '14 at 12:18

score 1 · Answer 1 · answered May 23 '14 at 11:54

1

float floatValue = 1.23455f;
String stringValue = Float.toString(floatValue).split("\\.")[1];

Should work for you

answered May 23 '14 at 11:54

PKlumpp

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You didn't escape the "." in the pattern. – Hot Licks May 23 '14 at 11:56
damn, this is a regex in java... I am doing too much python atm – PKlumpp May 23 '14 at 11:58
@ZerO Thanks for your answer but I think it is basically the same as mine. – jeojavi May 23 '14 at 12:12
no it's not. I used split. and you used a substring, which is just not needed – PKlumpp May 23 '14 at 12:16
This gives interesting results if the number is big enough for `Float.toString` to use scientific notation ("capital E" notation). – Dawood ibn Kareem May 23 '14 at 12:21
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@ZerO - Probably substring is better than split, since substring creates only the new String, while split creates 2 Strings and an array. – Hot Licks May 23 '14 at 15:36
but isn't it lost as I do not assign the array to any variable? – PKlumpp May 23 '14 at 16:07

Show only decimals of float

1 Answers1