·

Glyph inner product: vector · vector reduces to a scalar dot product.

Syntax: <expression> · <expression>

Category#

arithmetic

Related#

• vector
• matrix
• 张量

Examples#

radix/corpus/vector/glyph-dot.fab (canonical · operator-group)#

Glyph inner product: vector · vector reduces to a scalar dot product.

# =============================================================================
# · — glyph inner product (dot / matvec / matmul by rank).
# =============================================================================
#
# What this teaches:
#   • Dot product — `a · b` is the multiplicative-level inner-product glyph, dispatched by rank
#   • Vector · vector — same-width vectors reduce to a scalar dot product
#
# Common mistakes:
#   • mixing vector widths — `vector · vector` requires identical widths (inner dim contract)
#   • scalar operands — the glyph rejects plain numbers instead of silently multiplying
#
# See also: vector, matrix, tensor
# =============================================================================



# vector · vector → scalar dot product
#
# WHY: the `·` glyph is the rank-dispatched inner product. Rank-1 · rank-1 is
# the dot product: same width required, element type strict-equal. Rank-2
# matmul lives in glyph-matmul.fab.
#
# a = [1.0, 2.0, 3.0]  b = [4.0, 5.0, 6.0]
# a · b = 1*4 + 2*5 + 3*6 = 32.0
#
# EXPECTED stdout:
#   32.0

main {
    const vf32[3] a ← [1.0, 2.0, 3.0] ↦ vf32[3]
    const vf32[3] b ← [4.0, 5.0, 6.0] ↦ vf32[3]
    const f32 d ← a · b
    print d
}

Expected output:

32.0