LOG10(): Base 10 logarithm

<?Php
echo LOG10(5);// Output is 0.69897000433602
echo "<br>";
echo LOG10(-6);// Output is NAN
echo "<br>";
echo LOG10(0);// Output is -INF
echo "<br>";
echo LOG10(8.6);// Output is 0.93449845124357
?>

LOG10(X);

Example 1: Logarithmic Scale for Sound Intensity

<?php
$intensity = 0.001;  // Sound intensity in watts per square meter
$reference = 0.00001;  // Reference intensity
$decibels = 10 * log10($intensity / $reference);
echo "Sound intensity: $decibels dB";
?>

Example 2: Finding Log Base 10 of a Percentage

<?php
$percentage = 75;
$log_percentage = log10($percentage / 100);
echo "Logarithm base 10 of 75%: $log_percentage";
?>

Logarithm base 10 of 75%: -0.1249387366083

Example 3: Calculating Base-10 Logarithms of Positive Numbers

The log10() function computes the logarithm of a number with base 10. Here's a simple example:

<?php
echo log10(1000); // Logarithm base 10 of 1000
echo "<br>";
echo log10(10); // Logarithm base 10 of 10
?>

Example 4: Logarithms in Scientific Calculations

Base-10 logarithms are commonly used in scientific and engineering fields to represent large-scale measurements such as pH or decibels:

<?php
$intensity = 1000000; // Sound intensity
$decibels = 10 * log10($intensity);
echo "Decibels: " . $decibels;
?>

Example 5: Error Handling with log10()

Handle invalid input (e.g., negative numbers) when using log10():

<?php
$num = -10;
if ($num > 0) {
    echo log10($num);
} else {
    echo "Logarithm not defined for non-positive numbers.";
}
?>

Subhendu Mohapatra

Author & Instructor at plus2net

I write and maintain practical tutorials on Python, PHP, SQL, JavaScript, HTML, jQuery, and web development at plus2net. The tutorials focus on clear explanations, working examples, and code that readers can test and adapt while learning.

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