Question

I have the following code which splits a string of numbers (separated by a space) and then creates an array of floats :

//Split the string and then build a float array with the values.
String[] tabOfFloatString = value.split(" ");
int length = tabOfFloatString.length;
System.out.println("Length of float string is" + length);
float[] floatsArray = new float[length];
for (int l=0; l<length; l++) {
float res = Float.parseFloat(tabOfFloatString[l]);
    System.out.println("Float is " + res);
    floatsArray[l]=res;
}

The problem is that some of the values in the string are formatted with scientific notation – e.g they read -3.04567E-8.

What I want to do is end up with a float which does not contain the E number.

I have been reading this thread which suggests that I could use BigDecimal, however am unable to get this to work – is this the best approach or should I try something else ? How to convert a string 3.0103E-7 to 0.00000030103 in Java?

Answer 1

Below is your code slightly modified. As per me this works well and doesn’t actually cares he order of the exponents:

public void function() {
    String value = "123456.0023 -3.04567E-8 -3.01967E-20";
    String[] tabOfFloatString = value.split(" ");
    int length = tabOfFloatString.length;
    System.out.println("Length of float string is" + length);
    float[] floatsArray = new float[length];
    for (int l = 0; l < length; l++) {
        String res = new BigDecimal(tabOfFloatString[l]).toPlainString();
        System.out.println("Float is " + res);
        floatsArray[l] = Float.parseFloat(res);
    }

}