Found it!  It was done in 1990 by James E. Agenbroad, and is called "Difficult Characters."  It was presented as a paper at the 33rd International Congress of Asian and North African Studies in Toronto in 1990.  Agenbroad lists 866 conjunct characters.



--
Professor Dominik Wujastyk
,

Singhmar Chair in Classical Indian Society and Polity
,

University of Alberta, Canada
.

South Asia at the U of A:
 
sas.ualberta.ca



On Thu, 21 Feb 2019 at 07:23, Krishnaprasad G via INDOLOGY <indology@list.indology.info> wrote:
Dear Harry Spier
Thanks a lot this great. You helped me a lot.
Dear all before creating fonts I was searching a lot for the most used conjuncts in Sanskrit(not Vedic) but could not found, I am glad that Dominik Wujastyk is going to send the list and I am waiting for that. 
And for benefit of others, I am sharing all the important conjuncts here.

क्क क्त क्त्य क्त्व क्न क्न्य क्म क्य क्र क्र्य क्ल क्व क्ष क्ष्ण क्ष्म क्ष्म्य क्ष्य क्ष्व ख्य ग्ध ग्न ग्न्य ग्र ग्र्य ग्ल ग्व घ्न घ्न्य घ्य घ्र घ्र्य ध्व ङ्क ङ्ख ङ्ख्य ङ्क्त ङ्क्त्य च्च च्छ च्छ्र च्छ्व च्म च्य ज्ज ज्र ज्र्य ज्व ट्ट ट्त्रि ट्य ट्सु ट्स ठ्य ठ्र ठ्सु ड्ग ड्म ड्य ढ्व ढ्य ण्ण ण्म ण्य ण्व त्त त्त्य त्त्र त्थ थ्य त्न त्न्य न्त्र्य त्प त्प्र त्फ त्म त्म्य त्य त्र त्र्य त्व त्स त्स्न त्स्न्य त्स्य द्ग द्ग्र द्द द्द्य द्ध द्ब द्ब्र द्भ द्ध्य द्म द्य द्र द्र्य द्व द्व्य द्व्र  ध्न ध्न्य न्न न्न्य न्म न्य न्व प्त प्त्य प्न प्म प्य प्र प्ल प्स प्स्य ब्ज ब्द ब्द्य ब्ध ब्य ब्र भ्ण भ्न भ्य भ्र भ्व म्म म्ण म्ण्य म्य म्र म्ल म्व य्व र्ण्य र्ध्व र्व्य र्त्स्न्य ल्क ल्ग ल्प ल्म ल्य ल्ल ल्व व्य व्र श्च श्न श्म श्य श्र श्ल श्व ष्क ष्क्र ष्ट ष्ट्य ष्ट्र ष्ट्व ष्ठ ष्ठ्य ष्ण ष्प ष्प्र ष्म ष्य ष्व स्क स्ख स्त स्त्य स्थ स्थ्य स्न स्प्र स्फ स्म स्य स्र ह्ण ह्न ह्न्य ह्म ह्य ह्र ह्ल ह्व  


On Wed, Feb 20, 2019 at 8:53 AM Harry Spier <hspier.muktabodha@gmail.com> wrote:

Dear Krishnaprasad,
I've attached a pdf of 4 examples of the cluster ṭtr taken from the the paper transcripts of the IFP .  These are handwritten in  the 50's and 60's .  They are by different scribes and they all use virama.  I didn't find any in the IFP transcripts that had the tra underneath, but I stopped searching after these four.

Harry Spier

On Mon, Feb 18, 2019 at 9:15 PM Madhav Deshpande via INDOLOGY <indology@list.indology.info> wrote:
Dear Krishnaprasad Ji,

     I don't have access to a manuscript of Ṣaṭtriṃśattattvasandoha, but here is the title page of the printed book that does not use a cluster of "tra" hanging below "ṭ", but prints just "ṭ" with a virāma sign.

image.png
On the other hand, the title page of the edition in the Kashmir Text Series, uses such a vertical cluster:

image.png
However, it looks somewhat odd in its appearance to me.

Madhav M. Deshpande
Professor Emeritus
Sanskrit and Linguistics
University of Michigan
[Residence: Campbell, California]


On Mon, Feb 18, 2019 at 10:12 AM Madhav Deshpande <mmdesh@umich.edu> wrote:
Dear Krishnaprasad Ji,

     Great to see your progress.  A comment.  Some horizontal lines, like that न, look thicker than the top line and lines in some other characters.  The thickness should be uniform.  Similarly, the knot for न, म, भ etc. should look exactly the same, and it should look the same whether it appears in full or half forms of these characters.

Madhav M. Deshpande
Professor Emeritus
Sanskrit and Linguistics
University of Michigan
[Residence: Campbell, California]


On Mon, Feb 18, 2019 at 9:58 AM Krishnaprasad G via INDOLOGY <indology@list.indology.info> wrote:
Dear all 
Some more characters.
Thanks 
KP

On Thu 27 Dec, 2018, 8:11 PM Madhav Deshpande, <mmdesh@umich.edu> wrote:
Dear Krishnaprasad Ji,

     Thank you so much for this download link.  It is a wealth of useful resources.  With best regards,

Madhav M. Deshpande
Professor Emeritus
Sanskrit and Linguistics
University of Michigan
[Residence: Campbell, California]


On Wed, Dec 26, 2018 at 7:22 PM Krishnaprasad G <krishnaprasadah.g@gmail.com> wrote:
Thanks, everyone for supporting me giving feedbacks.

You can download from here.

On Thu, Dec 27, 2018 at 8:43 AM Harry Spier <hspier.muktabodha@gmail.com> wrote:
Dominink Wujastyk wrote: 
 modern font technology can help.  OpenType includes some "alternates" or "contextual alternates" features that allow the user (or auto-select) to select from multiple versions of a glyph.  But I'm sure you know this.  And it's only certain advanced text-setting programs like TeX that allow one to access such features easily (e.g., through fontspec, manual part IV).
 
I use the FontCreator program from Hi-Logic which allows you to create open type "contextual features".  I've used this feature. I use the professional product which retails for $199.00 but their website says that the Home edition for $79.00 also has this feature (but the home edition cannot be used for commercial purposes).  The program only works on windows.
 

Such questions make me wish to consult Naik's classic work Typography of Devanagari (3 vols, 1971 rev. ed.), but I've never had access to a copy of this rare publication.
 
I have this book. (Unfortunately its in storage in New York). Its been 20 years since I looked at it but I recall it was absolutely fascinating.  As I recall  one volume gives examples of devanagari printing from the earliest printed editions up till fairly modern times (when it was published), another volume  describes the authors ideas for a devanagari typewriter and the third volume focuses on some esoteric ideas of the author.  I can't recall the details.

Harry Spier


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