converting Double to string

KNIME Analytics Platform
1

string() doesn't convert a double to a string in the string manipulator node.

When I try use a Double.ToString in a Java Snippet it gives me a non-recurring decimal. When I use a groupby and concatenate it does the same. Is there anyway around this?

 

Thank you

Varun

2

Can you simply use the number to string node instead?

simon,

3

If you are getting long numbers of chracters after the decimal point, try using DecimalFormat or String.format to control the output in a Java Snippet.

Following links show how to use them
E.g.

or

http://examples.javacodegeeks.com/core-java/lang/string/java-string-format-example/ (See example 3 for String.format(…) syntax

Steve

4

Put this into the string manipulation node

string(toLong($YOUR_COLUMN$))

 

Cheers

1 Like
5

Hi All,

@richards99: I tried Number to String and the problem still prevails: 0.622 -> 0.62192744…
@andyg: Unfortunately when I try that it just returns the integer value.
@s.roughley: I haven’t programmed in Java ever and am unfamiliar with the language. However I did try

“”“
public class StringFormatExample{
public static void main(String[] args) {
System.out.printf(“Floating point number with 3 decimal digits: %.3f\n”,$COLUMN_NAME$);
}
}
”""
and it throws errors in a Java Snippet(simple) node.

Thank you for the replies everyone.

varun

6

Hi,

Your cell must contain a recurring decimal to start with, its probably that when the number is rendered on-screen, its automatically rounded off. Therefore;

Before using the Number to String node, use the Round Number node, and specify how decimal points or significant figures you wish your number to contain.

Simon.

7

Thank you Simon. That worked!

8

Top marks to Simon for my most-overlooked Round Number node.  For reference, in the Java Snippet(Simple) you need to set your return type to String, and then enter code something like:

Double dbl = $DblColumnName$;  //Select by double clicking your double column to get the format correct after the = sign

String r = String.format ("%.3f", dbl);
return r;

Steve

PS - The Java Snippet (Simple) node was where I first learnt to write Java!