Applies a function to the element at a given position.
MapAt[f, expr, n]
MapAt[f, expr, {i, j, …}]
MapAt[f, expr, {{i1, j1, …}, {i2, j2, …}, …}]
MapAt[f, pos]
MapAt[f, {a, b, c}, 2]
→ {a, f[b], c}MapAt[f, {{a, b, c}, {d, e, f}}, {All, 2}]
→ {{a, f[b], c}, {d, f[e], f}}MapAt[F, {a, b, c, d, e}, {Span[1, -1, 2]}]
→ {F[a], b, F[c], d, F[e]}{MapAt[f, g[x], {0}], MapAt[f, g[x][y], {0}], MapAt[f, g[x][y], {0, 1}]}
→ {f[g][x], f[g[x]][y], g[f[x]][y]}{MapAt[f, a -> b, {1}], MapAt[f, a -> b, {2}]}
→ {f[a] -> b, a -> f[b]}{MapAt[f, a == b, {1}], MapAt[f, a + b, {1}]}
→ {f[a] == b, b + f[a]}