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mock final

Here. (Disregard the points for the problems.)final_mock

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week 13

\(\def\Real{\mathbb{R}}
\def\Comp{\mathbb{C}}
\def\Rat{\mathbb{Q}}
\def\Field{\mathbb{F}}
\def\Fun{\mathbf{Fun}}
\def\e{\mathbf{e}}
\def\f{\mathbf{f}}
\def\bv{\mathbf{v}}
\)

Interior point methods

Logarithmic barriers. Central path. Convergence and quality of solution estimates from duality. (Boyd, chapt.11).

Ellipsoid method

(Use Boyd’s notes).


Sample problems

  • Find the central path for the
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week 12

\(\def\Real{\mathbb{R}}
\def\Comp{\mathbb{C}}
\def\Rat{\mathbb{Q}}
\def\Field{\mathbb{F}}
\def\Fun{\mathbf{Fun}}
\def\e{\mathbf{e}}
\def\f{\mathbf{f}}
\def\bv{\mathbf{v}}
\)

Conjugate gradient method

Material:Guler, ch. 14.7-9

Conjugate directions. Gram-Schmidt algorithm. Conjugate directions algorithm. Performance estimates via spectral data.


Sample problems

  • Consider the 4-dimensional space spanned by the polynomials
    \[
    p(x)=ax^3+bx^2+cx+d
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week 11

\(\def\Real{\mathbb{R}}
\def\Comp{\mathbb{C}}
\def\Rat{\mathbb{Q}}
\def\Field{\mathbb{F}}
\def\Fun{\mathbf{Fun}}
\def\e{\mathbf{e}}
\def\f{\mathbf{f}}
\def\bv{\mathbf{v}}
\)

Gradient descent methods. Step size choices. Backtracking rule.

Newton algorithm. Solving systems of nonlinear equations. Quadratic convergence,


Sample problems

  • Compute first 5 iterations \(x_0=2,x_1,\ldots, x_5 \) of Newton method to solve
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programming exercise 2

\(\def\Real{\mathbb{R}}
\def\Comp{\mathbb{C}}
\def\Rat{\mathbb{Q}}
\def\Field{\mathbb{F}}
\def\Fun{\mathbf{Fun}}
\def\e{\mathbf{e}}
\def\f{\mathbf{f}}
\def\bv{\mathbf{v}}
\)

Set \(d=18\).

Consider the \(d\times d\) matrix
\[
C=\left(c_{ij}\right)_{i,j}
\]
where
\[
c_{ij}=a_{ij}+n_i-n_j.
\]
The base matrix of coefficients \(a_{ij}, 1\leq i,j\leq d\) is given here; the modifier \(n_j\) is …

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week 10

\(\def\Real{\mathbb{R}}
\def\Comp{\mathbb{C}}
\def\Rat{\mathbb{Q}}
\def\Field{\mathbb{F}}
\def\Fun{\mathbf{Fun}}
\def\e{\mathbf{e}}
\def\f{\mathbf{f}}
\def\bv{\mathbf{v}}
\)

Simplex method

Tableau, pivot step, pivot rules. Exceptions. Phase one (finding a feasible point).


Sample problem

  1. For which \(h\) the following system is feasible?
    \[
    \begin{array}{ccc}
    &y&\leq 0\\
    x&&\geq 0\\
    x&-y&\leq
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Topologically constrained models of statistical physics.

\(\def\Real{\mathbb{R}}
\def\Int{\mathbb{Z}}
\def\Comp{\mathbb{C}}
\def\Rat{\mathbb{Q}}
\def\Field{\mathbb{F}}
\def\Fun{\mathbf{Fun}}
\def\e{\mathbf{e}}
\def\f{\mathbf{f}}
\def\bv{\mathbf{v}}
\def\blob{\mathcal{B}}
\)

The Blob

Consider the following planar “spin model”: the state of the system is a function from \(\Int^2\) into \(\{0,1\}\) (on and off states). We interpret the site \((i,j), …

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CDC’15

Slides are here.…

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Topology in Motion @ICERM Fall’16

If you are interested in Applied Topology, tend to plan far, far ahead and have some free time on your hands in Fall 2016, check this out, and let us know!

logo_tim

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math285, week of october 27

Read the textbook, chapters 9.1-9.3.

Many videos to watch.

Homework (due by Tuesday, 11.6):

  1. Find Fourier transform of the function on \((-\pi,\pi)\) equal to \(0\) for \(-\pi<x<0\) and to \(1\) for \(0\leq x<\pi\).
  2. Find cosine expansion of \(\sin(2x)\) on
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