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SAMATICA
In this chapter: Matrices and vectors
  1. Enter matrices, then add, subtract and multiply them
  2. Determinant, inverse and transpose of a matrix
  3. Rank, row reduction, trace and eigenvalues of a matrix
  4. Enter vectors, then take the dot and cross product
  5. Vector length, angle between vectors, unit vector, projection and distance

Vector length, angle between vectors, unit vector, projection and distance in Scientific calculator plus 991 for Android

On the 2nd keyboard, the linear algebra menu holds Norm for a vector's length, VectorAngle for the angle between two, Normalize for the unit vector and Projection for the shadow of one vector on another; SHIFT linear algebra (clustering) holds EuclideanDistance. In VECTOR Mode the MATH section has Angle, Normalize and Projection for stored vectors. Answers stay exact where they can: Norm((1, 2, 3)) is √14, and an angle comes in the angle unit that is set.

Length
Norm(v), exact where it can be
Angle
VectorAngle(u, v), in the angle unit set
Unit vector, projection
Normalize(v), Projection(vector1, vector2)
Distance
EuclideanDistance(u, v), under SHIFT linear algebra

These functions measure vectors rather than combine them: how long one is, the angle between two, the vector of length 1 in the same direction, the part of one vector that lies along another, and the distance between the points two vectors reach. They answer exactly where an exact answer exists, a square root left as a root and a fraction as a fraction.

Where they are

On the 2nd keyboard, the linear algebra key opens a searchable list of about sixty functions, Norm, VectorAngle, Normalize and Projection among them; type in the search box at the top to filter it. EuclideanDistance is in the other list on the same key, SHIFT linear algebra clustering. Put the vectors inside the brackets with the v2 and v3 templates, as on entering a vector.

The MATH section of VECTOR Mode's menu: Dot, Angle, Normalize, Cross and Projection.
The MATH section of VECTOR Mode's menu: Dot, Angle, Normalize, Cross and Projection.

In VECTOR Mode, the MATH section of the vector menu, SHIFT 5 VECTOR, lists Dot, Angle(vectorA,vectorB), Normalize(vector) (Unit Vector), Cross(vector1,vector2) and Projection(vector1, vector2), which take stored vectors by name. The manual's vectors on the 2nd keyboard are u = (1, 2, 3) and v = (1, 5, 7), a = (3, 4) and b = (1, 1).

Length

Norm(v) gives the length of a vector, the square root of the sum of the squares of its components.

The length of (3, 4)

in Norm((3, 4))

out 5

That is √(3² + 4²) = √25 = 5. Lengths are usually not whole numbers, and then the answer stays exact:

The length of (1, 2, 3)

in Norm((1, 2, 3))

out √14

Tap the result to switch between √14 and its decimal value.

The angle between two vectors

VectorAngle(u, v) gives the angle between two vectors, in the angle unit currently set, so check the unit before you read the answer. The examples here are in Degree.

Half a right angle apart

in VectorAngle((1, 1), (1, 0))

out 45

Two perpendicular vectors give exactly a right angle. (3, 4) and (−4, 3) are perpendicular:

Perpendicular in the plane

in VectorAngle((3, 4), (-4, 3))

out 90

The same holds in three dimensions. (1, 2, 3) and (1, 1, −1) have a dot product of 0, so they are perpendicular too:

Perpendicular in space

in VectorAngle((1, 2, 3), (1, 1, -1))

out 90

In VECTOR Mode the function is the MATH section's Angle(vectorA,vectorB): choose it, then the two vectors from NAMES with SHIFT ) , between them. The row is named Angle, but it types VectorAngle( on the input line.

Angle from the MATH section types VectorAngle(. With VctC = (2, −1, 2) and VctD = (1, 0, −1) the answer is 90, in Degree.
Angle from the MATH section types VectorAngle(. With VctC = (2, −1, 2) and VctD = (1, 0, −1) the answer is 90, in Degree.
Angle from the MATH section, on VctC and VctD

in VectorAngle(VctC,VctD)

out 90

Unit vector

Normalize(v) scales a vector to length 1 while keeping its direction. (3, 4) has length 5, so each component is divided by 5:

The unit vector along (3, 4)

in Normalize((3, 4))

out {(3/5), (4/5)}

Tap the result to switch between the exact fractions 3/5 and 4/5 and the decimals 0.6 and 0.8. In VECTOR Mode it is the MATH section's Normalize(vector) (Unit Vector).

Projection

Projection(vector1, vector2) gives the shadow of the first vector along the direction of the second: the part of vector1 that points the way vector2 does. Its components are kept as fractions.

u projected onto v

in Projection((1, 2, 3), (1, 5, 7))

out {(32/75), (32/15), (224/75)}

In VECTOR Mode, with the manual's VctA = (1, 2) and VctB = (3, 4), the MATH section's Projection(vector1, vector2) gives:

VctA projected onto VctB

in Projection(VctA,VctB)

out {(33/25), (44/25)}

The order matters: the first vector is the one projected, the second only gives the direction.

Distance between two points

EuclideanDistance(u, v) gives the straight-line distance between the two points the vectors point to. It is in the clustering list, SHIFT linear algebra clustering, not the main linear algebra list.

SHIFT and the linear algebra key: the clustering list, where EuclideanDistance is.
SHIFT and the linear algebra key: the clustering list, where EuclideanDistance is.
From (3, 4) to (1, 1)

in EuclideanDistance((3, 4), (1, 1))

out √13

That is √((3 − 1)² + (4 − 1)²) = √13.

Before you read an answer

  • The angle unit. VectorAngle, and Angle in VECTOR Mode, answer in the unit that is set; the indicator on the display shows which.
  • The template. The template key on its own, [::], inserts a matrix, not a vector. A one-row matrix looks exactly like a vector on screen, so keep to v2 and v3 for vector work.
  • Exact or decimal. A root or a fraction in an answer switches to its decimal value, and back, with a tap on the answer.

At a glance

FunctionWhereWhat it gives
Norm(v)linear algebraThe length of a vector
VectorAngle(u, v)linear algebra; Angle in VECTOR Mode's MATHThe angle between two vectors, in the angle unit set
Normalize(v)linear algebra; MATHThe unit vector in the same direction
Projection(vector1, vector2)linear algebra; MATHThe projection of the first onto the second
EuclideanDistance(u, v)SHIFT linear algebra clusteringThe distance between two points

Questions

How do I find the length of a vector?

Choose Norm(v) from the linear algebra menu on the 2nd keyboard and put the vector inside. Norm((3, 4)) is 5, that is √(3² + 4²). A length that is not a whole number stays exact: Norm((1, 2, 3)) is √14, and a tap on the answer switches it to its decimal value.

How do I find the angle between two vectors?

Use VectorAngle(u, v) from the linear algebra menu on the 2nd keyboard; in VECTOR Mode it is the MATH section's Angle(vectorA,vectorB), which types VectorAngle(. The answer is in the angle unit currently set, so check it first: in degrees, (1, 1) and (1, 0) are 45 apart, and (3, 4) and (−4, 3) are 90 apart.

How do I get a unit vector?

Normalize(v) scales a vector to length 1 and keeps its direction. (3, 4) has length 5, so Normalize((3, 4)) is (3/5, 4/5); tap the answer to switch between those fractions and 0.6 and 0.8.

Can it find the distance between two points?

Yes: EuclideanDistance(u, v), from the clustering menu (SHIFT and the linear algebra key on the 2nd keyboard), gives the straight-line distance between the two points the vectors point to. For (3, 4) and (1, 1) it is √13, that is √((3 − 1)² + (4 − 1)²).

Related pages

Written from the calculator's own manual and from the app itself, version 7.6.0; every figure is one the manual shows or a capture of the app proves. Last revised on 29 September 2026.

Bug reports and feature requests go to kimcuc@samatica.com — a person reads it.