<img src="https://media.daily.dev/image/upload/s--oGk3DeXI--/f_auto/v1720901158/ugc/content_fb9cf0ed-dad5-42a3-b046-00e4cfb12ba3" alt="image">
They said that we’d need math for programming. Look where that landed us ¯\(ツ)/¯

The Watercooler Squad is an important place for all things unimportant and nonsense at daily.dev. It’s designed to waste your time and distract you, buckle up 😻 🤹🏽‍♀️

Watercooler

Math in CS vs Reality

parseInt’s behavior stems from the interplay of JavaScript’s number representation and its parsing logic.
<ul>
<li>JavaScript’s Number Type: JavaScript uses a double-precision floating-point format to represent numbers. This format has limitations in accurately representing very small or very large numbers. It also uses a specific notation for scientific numbers (e.g., 1e-6).</li>
<li>parseInt’s Purpose: The function is designed to extract integer values from strings. It first converts the input string into a number, then truncates any fractional part to obtain the integer.</li>
<li>The Cases:
<ul>
<li>0.00001: This is treated as a regular decimal number. After conversion, its integer part is 0, so parseInt returns 0.</li>
<li>0.000001: Due to JavaScript’s number representation, this value is internally represented as 1e-6 (scientific notation). When parseInt encounters this format, it recognizes the ‘e’ as an exponent indicator and extracts the base number (1) as the integer part, discarding the exponent and returning 1.
In Summary:
parseInt’s seemingly inconsistent behavior is due to the interaction between:</li>
</ul>
</li>
<li>JavaScript’s number representation: Small decimal values may be represented in scientific notation.</li>
<li>parseInt’s logic: It extracts the integer part after converting the input to a number, which can lead to different interpretations for regular decimals and scientific notation.
Key Points:</li>
<li>parseInt is not intended for precise handling of floating-point numbers.</li>
<li>For handling fractional values, consider using parseFloat or other methods specifically designed for floating-point operations.</li>
<li>Understanding JavaScript’s number representation is crucial for interpreting the behavior of functions like parseInt.</li>
</ul>

My general understanding of floating point numbers is don’t use them for critical calculations. I’ve even read some annoying workarounds for this in JS by converting all decimal numbers to integers and then dividing the result by the total scale to get an “accurate” decimal representation.