But, if you fix a point, then we have linear approximation.

但是，如果你固定了一个点，就能得到线性近似。

youdao

Sets the pixel at the specified point to the closest approximation of the specified color.

设置指定点像素为最接近指定色的近似值。

youdao

Thus, encoding an image by fractal techniques consists of finding an appropriate contractive transformation whose fixed point is the best possible approximation of the original image.

因此，一幅图像的分形编码就是寻找一个合适的压缩仿射变换，它的不动点是原始图像尽可能好的近似。

youdao

The first step is simply for a player to note the time it takes for the ball to pass a fixed point to get a rough approximation of the velocity of the ball.

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