tan - gehrigwilcox/C-Standard-Library GitHub Wiki
Tangent is the ratio between the y and x position on the unit circle.
{
"width": 200,
"height": 200,
"data": {
"sequence": {
"start": 0,
"stop": 6.28,
"step": 0.01,
"as": "theta"
}
},
"transform": [
{
"calculate": "cos(datum.theta)",
"as": "x"
},
{
"calculate": "sin(datum.theta)",
"as": "y"
}
],
"mark": "line",
"encoding": {
"x": {
"type": "quantitative",
"field": "x"
},
"y": {
"field": "y",
"type": "quantitative"
}
}
}
Since sine gives us the y position, and cosine gives us the x position, tangent is the relationship between sine and cosine. Mathematically,
In C:
return sin(x)/cos(x);