Java printing symbol for positive number

Question

I have a Java program that does a bunch of calculations from some user inputs and at the end it has to print the equation of the plane. Format of the equation of the plane is 6x-2y+3z-4=0.

To get the values 6, -2, 3, & -4 is from a bunch of calculations. So i was thinking to print out the equation is to

System.out.println("Equation is: " + aa + "x" + bb +
"y" + cc + "z" + gg + "=0");

Where aa, bb, cc , gg corresponds to the 4 integers above. But the output is

Equation is: 6x-2y3z-4=0

It seems to print the minus signs in there for the negative numbers but how can i have it print out a plus sign if the number is positive? Like in between -2y3z should be 6x-2y+3z-4=0

http://stackoverflow.com/questions/5243316/format-a-number-with-leading-sign — Dineshkumar, Apr 08 '14 at 05:09
well what if it wasn't the z variable that was positive but instead it was the y variable? or what if it was all variables plus the constant that were positive? h — Selena Gomez, Apr 08 '14 at 05:09
http://docs.oracle.com/javase/tutorial/java/data/numberformat.html — Dineshkumar, Apr 08 '14 at 05:12

score 6 · Accepted Answer · answered Apr 08 '14 at 05:10

You could use System.format():

System.out.format("Equation is: %dx %+dy %+dz %+d = 0\n", aa, bb, cc, gg);
                                     ^    ^    ^

Specifying the + flag would include the sign whether positive or negative.

You can find more information about formatting numeric output here.

score 3 · Answer 2 · answered Apr 08 '14 at 05:11

You can try using printf() to display a formatted output:

int aa = 6;
int bb = -2;
int cc = 3;
int gg = -4;

System.out.printf("Equation is: %dx%+dy%+dz%+d=0", aa, bb, cc, gg);

Here you are ussing the format modifier %+d, to specify that the sign must be displayed, even if the number is positive.

Output:

Equation is: 6x-2y+3z-4=0

score 0 · Answer 3 · answered Apr 08 '14 at 05:11

you need to add + in your string for positive numbers. you can do something like following. So better take a string and add your variables there. While adding consider following three things

if the variable is 0 dont add that part at all.
if the variable is positive add a '+' then the variable
if the variable is negative just add the variable

Java printing symbol for positive number

3 Answers3