Unable to save a value of 0 for FORMAT_TYPE_F variables. It gets written as a blank value every time. No luck using the values array.

[ghost]

I can't get the library to export actual zero values for variables with the format Variable::FORMAT_TYPE_F. Instead, the library is converting all 0 values to blanks when writing the SPSS file. Here is some sample code that will illustrate the point.

$file = '<path>'
$data = [
    'header' => [
        'creationDate' => '01 01 2020',
        'creationTime' => '01:01:01',
    ],
    'variables' => [
        [
            'name'       => 'TEST_VAR',
            'format'     => Variable::FORMAT_TYPE_F,
            'width'      => 40,
            'decimals'   => 2,
            'label'      => 'TEST LABEL',
            'values'     => [],
            'columns'    => 5,
            'alignment'  => Variable::ALIGN_RIGHT,
            'measure'    => Variable::MEASURE_SCALE,
            'attributes' => [
                '$@Role' => Variable::ROLE_INPUT,
            ],
            'data'       => [1,0,2,3,4,0,5],
        ]
    ],
];

$writer = new Writer($data);
$writer->save($file);

If I write this to a file the responses with '0' as the value will be blank, not the number 0. I've tried adding the following:

'values' => ['0' => '0'],

and

'values' => ['0.00' => '0'],

I've tried other variations with and with out quotes and some end up creating a corrupt SPSS file and the others didn't work as well. I've also tried making sure the zeroes in the data array are entered as 0.00 but that did not work either.

I'm imagine I must be missing something but this appears to be a bug. Thanks in advance for your time!

[lestcape]

@davechez I think that is what is expected to happen, let me explain.

I added an info section to your example for a better explanation in the data variable in this way:

$file = '<path>';
$data = [
    'header' => [
        'creationDate' => '01 01 2020',
        'creationTime' => '01:01:01',
    ],
    'info' => [
        'machineFloatingPoint' => [
            'sysmis' => -1.7976931348623157e+308,
            'highest' => 1.7976931348623157e+308,
            'lowest' => -1.7976931348623155e+308,
        ],
    ],
    'variables' => [
        [
            'name'       => 'TEST_VAR',
            'format'     => Variable::FORMAT_TYPE_F,
            'width'      => 40,
            'decimals'   => 2,
            'label'      => 'TEST LABEL',
            'values'     => [],
            'columns'    => 5,
            'alignment'  => Variable::ALIGN_RIGHT,
            'measure'    => Variable::MEASURE_SCALE,
            'attributes' => [
                '$@Role' => Variable::ROLE_INPUT,
            ],
            'data'       => [1,0,2,3,4,0,5],
        ]
    ],
];

$writer = new Writer($data);
$writer->save($file);

As you can see I set a sysmis value and if i don't set it, it will be 0 as your own example case. The sysmis tell to the sav file what is the numeric value that should be interpreted as a missing value. So, as you don't set any value 0 is assumed as the system missing value and that is why you get it always as a blank value every time.

In my example, I set a sysmis different to 0, so now i can set 0 and and read it as 0 instead of blank. If in my example I need to set a missing value, i have two options. I need to use the sysmis that i defined or i can set an empty string ''. So if i need a missing value in the first position i can do:

 'data'       => ['',0,2,3,4,0,5],

This is possible because of this condition, but probably will be good to add also a check for a php null value to that line. Something like:

} elseif ($value === $sysmis || '' === $value || !isset($value)) {

and then this can help us to defined the data in a more common way as:

 'data'       => [null,0,2,3,4,0,5],

It's also important to mention that when you are reading you sav file you also need to read the sysmis value that is set in the file header:

public function getSystemMissingValue() {
    $subType = SPSS\Sav\Record\Info\MachineFloatingPoint::SUBTYPE;
    if (isset($this->savReader) && isset($this->savReader->info) && isset($this->savReader->info[$subType])) {
        return $this->savReader->info[$subType]->sysmis;
    }
    return null;
}

and then check what value is a missing value in your data, otherwise the missing values will appeared as the value of the sysmis and probably this is not what you want to occurs in your app. I hope this will help you.