src/tweene.js
function parseSpeed(value)
{
    if(value in speeds)
    {
        value = speeds[value];
    }

    value = parseFloat(value);
    if(isNaN(value) || !value || value <= 0)
    {
        value = 1;
    }
    return value;
}
function parseSpeed(value)
{
    if(value in speeds)
    {
        value = speeds[value];
    }

    value = parseFloat(value);
    if(isNaN(value) || !value || value <= 0)
    {
        value = 1;
    }
    return value;
}
function parseSpeed ( value ) { if ( value in speeds ) { value = speeds [ value ] ; } value = parseFloat ( value ) ; if ( isNaN ( value ) || ! value || value <= 0 ) { value = 1 ; } return value ; }
accept a speed name shortcuts or a number and give back an acceptable positive value.
Fallback to 1 if value is out of valid range

@param {string|number} value
@returns {number}
accept a speed name shortcuts or a number and give back an acceptable positive value . Fallback to 1 if value is out of valid range