Clamp (function)
In computer science, clamping, or clipping is the process of limiting a value to a range between a minimum and a maximum value. Unlike wrapping, Clamping moves a value to the nearest boundary if it is outside the allowed range. In Python, clamping can be defined as follows: This is equivalent to max(minimum, min(x, maximum)) for languages that support the functions min and max.
 | This article needs additional citations for verification. (December 2009) |
In computer science, clamping, or clipping is the process of limiting a value to a range between a minimum and a maximum value. Unlike wrapping, Clamping moves a value to the nearest boundary if it is outside the allowed range.
| Y = clamp(X, 1, 3) | |
|---|---|
| X | Y |
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 3 |
In Python, clamping can be defined as follows:
def clamp(x, minimum, maximum):
if x < minimum:
return minimum
if x > maximum:
return maximum
return x
This is equivalent to max(minimum, min(x, maximum)) for languages that support the functions min and max.
Uses
[edit]Several programming languages and libraries provide functions for fast and vectorized clamping. In Python, the pandas library offers the Series.clip[1] and DataFrame.clip[2] methods. The NumPy library offers the clip[3] function. In the Wolfram Language, it is implemented as Clip[x, {minimum, maximum}].[4]
In OpenGL, the glClearColor function takes four GLfloat values which are then 'clamped' to the range .[5]
![{\displaystyle [0,1]}](https://wikimedia.org/api/rest_v1/media/math/render/svg/738f7d23bb2d9642bab520020873cccbef49768d)
One of the many uses of clamping in computer graphics is the placing of a detail inside a polygon—for example, a bullet hole on a wall. It can also be used with wrapping to create a variety of effects.
In CSS, clamp()[6] can help to implement responsive typography or responsive designs generally.[7]
Although spreadsheets like Excel, Open Office Calc, or Google Sheets don't provide a clamping function directly, the same effect can be achieved by using functions like MAX & MIN together, by MEDIAN,[8][9] or with cell function macros.[10] When attempting to do a clamp where the input is an array, other methods must be used.[11]
References
[edit]- ^ "Pandas Series.clip method documentation". Retrieved 2023-10-15.
- ^ "Pandas DataFrame.clip method documentation". Retrieved 2023-10-15.
- ^ "NumPy clip function documentation". Retrieved 2023-10-15.
- ^ "Wolfram Language Clip function documentation". Retrieved 2023-10-15.
- ^ "OpenGL 4 Reference Pages". www.khronos.org. Retrieved 2018-10-31.
- ^ "clamp()". MDN Web Docs. Mozilla.
- ^ Bece, Adrian. "Modern Fluid Typography Using CSS Clamp". Smashing Magazine. Smashing Media AG. Retrieved 29 January 2025.
- ^ Citi, Jasper. "How do I constrain a value to a range in excel?". Stack Overflow. Retrieved 29 January 2025.
- ^ "Clamp function in Excel". Excel Forum. Retrieved 29 January 2025.
- ^ "[Solved] Math Clamp Function?". Apache OpenOffice Community Forum. Retrieved 29 January 2025.
- ^ "Array-Safe Clamp Value in Google Sheets". Stack Exchange > Web Applications. Stack Overflow. Retrieved 29 January 2025.
Further reading
[edit]- Apodaca, Anthony A.; Gritz, Larry (Dec 1999). Advanced RenderMan: Creating CGI for Motion Pictures. Morgan Kaufmann.
 | This computer graphics–related article is a stub. You can help Wikipedia by adding missing information. |