# Answers for "php float precision"

1

php float precision

<?php
var_dump(round(3.4)); // =>3
var_dump(round(3.5)); // =>4
var_dump(round(3.6)); // =>4
var_dump(round(3.6, 0)); // =>4
var_dump(round(5.045, 2)); // =>5.05
var_dump(round(5.055, 2)); // =>5.06
var_dump(round(345, -2)); // =>300
var_dump(round(345, -3)); // =>0
var_dump(round(678, -2)); // =>700
var_dump(round(678, -3));  // =>1000
?>
Posted by: Guest on December-03-2020
3

php float value

floatval (\$var)
Posted by: Guest on June-19-2019
0

php rounded to the nearest degree time with ms calculator

For people interest in Differential Equations, I've done a function that receive a string like: x^2+x^3 and put it in
2x+3x^2 witch is the differantial of the previous equation.

In the code there is one thing missing: the \$string{\$i} is often going outOfBound (Uninitialized string offset: 6 in...)
if your error setting is set a little too high... I just dont know how to fix this.

So there is the code for differential equation with (+ and -) only:

<?
function differentiel(\$equa)
{
\$equa = strtolower(\$equa);
echo "Equation de depart: ".\$equa."<br>";
\$final = "";

for(\$i = 0; \$i < strlen(\$equa); \$i++)
{
//Make a new string from the receive \$equa
if(\$equa{\$i} == "x" && \$equa{\$i+1} == "^")
{
\$final .= \$equa{\$i+2};
\$final .= "x^";
\$final .= \$equa{\$i+2}-1;
}
elseif(\$equa{\$i} == "+" || \$equa{\$i} == "-")
{
\$final .= \$equa{\$i};
}
elseif(is_numeric(\$equa{\$i}) && \$i == 0)
{
//gerer parenthese et autre terme generaux + gerer ^apres: 2^2
\$final .= \$equa{\$i}."*";
}
elseif(is_numeric(\$equa{\$i}) && \$i > 0 && \$equa{\$i-1} != "^")
{
//gerer ^apres: 2^2
\$final .= \$equa{\$i}."*";
}
elseif(\$equa{\$i} == "^")
{
continue;
}
elseif(is_numeric(\$equa{\$i}) && \$equa{\$i-1} == "^")
{
continue;
}
else
{
if(\$equa{\$i} == "x")
{
\$final .= 1;
}
else
{
\$final .= \$equa{\$i};
}
}
}
//
//Manage multiplication add in the previous string \$final
//
\$finalMul = "";
for(\$i = 0; \$i < strlen(\$final); \$i++)
{
if(is_numeric(\$final{\$i}) && \$final{\$i+1} == "*" && is_numeric(\$final{\$i+2}))
{
\$finalMul .= \$final{\$i}*\$final{\$i+2};
}
elseif(\$final{\$i} == "*")
{
continue;
}
elseif(is_numeric(\$final{\$i}) && \$final{\$i+1} != "*" && \$final{\$i-1} == "*")
{
continue;
}
else
{
\$finalMul .= \$final{\$i};
}
}
echo "equa final: ".\$finalMul;
}
?>

I know this is not optimal but i've done this quick :)
If you guys have any comment just email me.
I also want to do this fonction In C to add to phpCore maybe soon...
Patoff
Posted by: Guest on February-04-2020